Does the halogen bonding interaction co-exist in liquid when it competes with the hydrogen bonding interaction？ The classical molecular dynamics simulations for the solvation properties of CLF molecule in water are p...Does the halogen bonding interaction co-exist in liquid when it competes with the hydrogen bonding interaction？ The classical molecular dynamics simulations for the solvation properties of CLF molecule in water are performed with the Lennard-Jones plus Coulomb electrostatic potential parameters that are optimized with ab initio interaction energy calculations for the pre-reactive H2O-CLF complex. We find that the halogen bonding interactions occur between O and CL atoms and have the comparable strength and population with respect to the hydrogen bonding interactions of C1...H.展开更多
A new complex, [Ni2（L）4（H2O）8]（1, L1 = 4-（1H-imidazol-4-yl）benzoic acid）, has been hydrothermally prepared and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and PXRD. C...A new complex, [Ni2（L）4（H2O）8]（1, L1 = 4-（1H-imidazol-4-yl）benzoic acid）, has been hydrothermally prepared and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and PXRD. Complex 1 crystallizes in monoclinic, space group P21/c with α = 22.281（2）, b = 7.3959（7）, c = 24.978（3） ？, β = 90.876（10）, V = 4115.6（7） ？3, Z = 8, C20H22N4O8Ni, Mr = 505.13, Dc = 1.630 g/cm3, μ = 1.001 mm-1, S = 1.080, F（000） = 2096, the final R = 0.452 and wR = 0.1152 for 9380 observed reflections （I 〉 2σ（I））. The result of X-ray diffraction analysis revealed three different kinds of Ni（II） centre mononuclear molecules in the asymmetric unit. The independent mononuclear units are bridged to form a three-dimensional supramolecular polymer by extensive hydrogen bonds and C–H… non-covalent bonding interactions.展开更多
Removing H_(2)S and CO_(2)is of great significance for natural gas purification.With excellent gas affinity and tunable structure,ionic liquids(ILs) have been regarded as nontrivial candidates for fabricating polymer-...Removing H_(2)S and CO_(2)is of great significance for natural gas purification.With excellent gas affinity and tunable structure,ionic liquids(ILs) have been regarded as nontrivial candidates for fabricating polymer-based membranes.Herein,we firstly reported the incorporation of protic ILs (PILs) having ether-rich and carboxylate sites (ECPILs) into poly(ether-block-amide)(Pebax) matrix for efficient separation H_(2)S and CO_(2)from CH_(4).Notably,the optimal permeability of H_(2)S reaches up to 4310 Barrer (40C,0.50 bar) in Pebax/ECPIL membranes,along with H_(2)S/CH_(4)and (H_(2)StCO_(2))/CH_(4)selectivity of 97.7 and 112.3,respectively.These values are increased by 1125%,160.8%and 145.9%compared to those in neat Pebax membrane.Additionally,the solubility and diffusion coefficients of the gases were measured,demonstrating that ECPIL can simultaneously strengthen the dissolution and diffusion of H_(2)S and CO_(2),thus elevating the permeability and permselectivity.By using quantum chemical calculations and FT-IR spectroscopy,the highly reversible multi-site hydrogen bonding interaction between ECPILs and H_(2)S was revealed,which is responsible for the fast permeation of H_(2)S and good selectivity.Furthermore,H_(2)S/CO_(2)/CH_(4)(3/3/94 mol/mol) ternary mixed gas can be efficiently and stably separated by Pebax/ECPIL membrane for at least 100 h.Overall,this work not only illustrates that PILs with ether-rich and carboxylate hydrogen bonding sites are outstanding materials for simultaneous removal of H_(2)S and CO_(2),but may also provide a novel insight into the design of membrane materials for natural gas upgrading.展开更多
Hydrogen bonding interaction in hydrogen fluoride dimer has been investigated by quan- tum-chemical calculation with 6-311G^(**) basis set at various mutual orientations.Atomic charges and charge transfer have been ca...Hydrogen bonding interaction in hydrogen fluoride dimer has been investigated by quan- tum-chemical calculation with 6-311G^(**) basis set at various mutual orientations.Atomic charges and charge transfer have been calculated by means of potential-derived method,and decomposition of hydro- gen bonding interaction has been executed.The calculation results show that there is a variation range for the energy-stable orientations,the charge transfer in the range presents maximum value,and the charge transfer interaction plays a decisive role in the hydrogen bonding.展开更多
Four micro states of Fe-CO with 3d(sigma)-4s and 3d(delta)-3d(delta) electrons spin-paired or unpaired are examined to investigate the influence of pairing versus unpairing mechanism upon the bondings and interactions...Four micro states of Fe-CO with 3d(sigma)-4s and 3d(delta)-3d(delta) electrons spin-paired or unpaired are examined to investigate the influence of pairing versus unpairing mechanism upon the bondings and interactions in Fe-CO. The calculation results show that the Fe-CO bondings and interactions are determined by a balance between the bonding stabilization and the exchange stabilization with or without 3d(sigma)-4s electron spin-pairing. The 3d(delta)-3d(delta) electron spin-pairing versus unpairing has a surprising large effect on the Fe-CO bonding properties, even though the 3d(delta) orbitals are usually considered as being nonbonding.展开更多
Oxygen release from Ni-rich cathode is one of the major structural degradations resulting in rapid performance fading in lithium-ion batteries(LIBs).The energy gap between the transition metals(TM)-d band and the O-p ...Oxygen release from Ni-rich cathode is one of the major structural degradations resulting in rapid performance fading in lithium-ion batteries(LIBs).The energy gap between the transition metals(TM)-d band and the O-p band serves as an effective evaluation metric in characterizing the potential for oxygen release.Given that the primary oxidation factors of NCM811 materials vary at different states of charge(SOC),this study employs high-throughput density functional theory(DFT)calculations combined with machine learning(ML)to systematically investigate the regulation mechanism of heteroatoms on the energy gap between the TM-d band(TM=Ni,Co)and O-p band at various SOC levels.Highthroughput DFT calculations were used to study doping thermodynamic stability and complete the database.The results indicate that dopant atoms remain at their original sites even at 50%SOC.Correlation analysis reveals that at 0 SOC,the dopant reduces Ni-O bonding interactions by forming its own bonds with oxygen,thereby preventing lattice oxygen escape and weakening the oxygen binding of the system during Ni redox.At 50%SOC,the dopant and Co atoms synergistically strengthen their bonding interactions with oxygen,thereby maintaining structural stability and inhibiting lattice oxygen escape.Based on R^(2)and root-mean-square error(RMSE),the gradient boosting regression(GBR)algorithm is identified as optimal for predicting the energy gaps between the Ni-d band and O-p band,as well as between the Co-d band and O-p band.Feature importance analysis demonstrates that the magnetic moment(Dma)of the doped atom significantly contributes to the prediction of ΔNi-O and ΔCo-O.In this study,the energy gap regulation mechanisms of Ni-d/O-p and Co-d/O-p are systematically investigated using non-empirical first principle calculations combined with data-driven machine learning,aiming to provide insights into the electrochemical stability of NCM811 and related materials.展开更多
According to the Kamlet-Abraham-Taft(KAT)polarity parameters(α,β,π*),polymers and solvents can be categorized as hydrogen-bond(H-bond)acidic(α>β)or H-bond basic(α<β).Recently,we proposed a quantitative hy...According to the Kamlet-Abraham-Taft(KAT)polarity parameters(α,β,π*),polymers and solvents can be categorized as hydrogen-bond(H-bond)acidic(α>β)or H-bond basic(α<β).Recently,we proposed a quantitative hydrogen bonding(QHB)analysis to predict the solubility of polymers in ionic liquids(ILs)using the product ofΔαΔβ<0 as an indicator,whereΔαis the difference between the H-bond acidic parameters of the polymer and IL,andΔβis the difference in their basicity,while the prerequisite of the“complementary”principle(i.e.,that one component is H-bond acidic and the other is basic)is satisfied.Here,the applicability of QHB analysis was first confirmed by testing the solubilities of carefully chosen polymer/deep eutectic solvent(DES)pairs,as the DESs were eutectic mixtures dominated by hydrogen bonding interactions.Then,our attention focused on the solubility of cellulose in DESs.Our testing results as well as the typical published results were summarized,which indicate that the potential DESs for cellulose dissolution and regeneration must be of the H-bond basic type because the“complementary”principle should be satisfied as a prerequisite.However,the H-bond basic DESs investigated in this study do not show the superior solubility of cellulose that has been commonly observed for H-bond basic ILs,even if the criterion ofΔαΔβ<0 is satisfied for both DESs and ILs.Possible reasons for this discrepancy are given to understand the varying effectiveness in cellulose dissolution for H-bond basic DESs and ILs.展开更多
The crystallization behavior of polyamide 6,6(PA66) under complex flow field is of great importance for its final mechanical properties.Poly(vinyl pyrrolidone)(PVP) was applied as crystallization modifying agency to i...The crystallization behavior of polyamide 6,6(PA66) under complex flow field is of great importance for its final mechanical properties.Poly(vinyl pyrrolidone)(PVP) was applied as crystallization modifying agency to improve processability of PA66.The regulation nature on hydrogen bonds(H-bonds) interaction of PVP was studied upon cooling process.As revealed by in situ FTIR,the sample with 5 wt% PVP displays decreased enthalpy change(ΔH) for both the generation of H-bonds and the transition of H-bonds from “disordered” to “ordered” state,which illustrates the molecular mechanism for the regulation of crystallzation behavior.Moveover,2D-WAXD is applied to reveal the evolution of microstructure for sample under external injection field.Hermans orientation factor(f_(H)) decreases obviously with the addition of PVP,because the relaxation of chain segments is promoted as well the crystallization is retarded.The above crystallization and microstructure changes during the processing provokes the improvement of processability without the apparent sacrifice of mechanical properties.展开更多
The through--space and through--bond interactions in 1, 5 -- Cyclooctadiyne are studied. It is shown, with the assistance of improved MS--X_α method, that the through- space interactions decrease with the distance of...The through--space and through--bond interactions in 1, 5 -- Cyclooctadiyne are studied. It is shown, with the assistance of improved MS--X_α method, that the through- space interactions decrease with the distance of the orbitals, and both through--space and through--bond interactions of 1, 5- Cyclooctadiyne are sizable but those two interactions oppose each other causing the net splitting to be small for π_z orbital. The calculated ionization potentials are in good agreement with the experiment of photoelectron spectra.展开更多
A series of soy protein isolate(SPI)films plasticized by glycerol(Gly)were studied using attenuated total reflectance-Fourier transform infrared spectroscopy(ATR/FTIR).Perturbation-correlation movingwindow two-dimensi...A series of soy protein isolate(SPI)films plasticized by glycerol(Gly)were studied using attenuated total reflectance-Fourier transform infrared spectroscopy(ATR/FTIR).Perturbation-correlation movingwindow two-dimensional(PCMW2D)and two-dimensional correlation(2DCOS)analyses were applied to the amideⅠband and thus the hydrogen bond interaction between SPI and Gly was systematically investigated.When Gly concentrations were in the range 0~35%,the hydrogen bond amongβ-sheets was replaced by the one between SPI chain and Gly molecule,which caused these protein chains being changed toα-helix.However,the transformation ofβ-sheet toα-helix was saturated and both of them tend to change to random coil when Gly concentrations were in the range 35%~60%.展开更多
Under solvothermal conditions,six new coordination polymers(CPs)[Mn(L)(phen)(H_(2)O)]_(n)(1),[Co(L)(phen)(H_(2)O)]_(n)(2),[Cu(L)(phen)(H_(2)O)]_(n)(3),[Zn_(2)(L)_(2)(phen)2(H_(2)O)]_(n)(4),[Zn(L)(phen)]_(n)(5),and[Cd(...Under solvothermal conditions,six new coordination polymers(CPs)[Mn(L)(phen)(H_(2)O)]_(n)(1),[Co(L)(phen)(H_(2)O)]_(n)(2),[Cu(L)(phen)(H_(2)O)]_(n)(3),[Zn_(2)(L)_(2)(phen)2(H_(2)O)]_(n)(4),[Zn(L)(phen)]_(n)(5),and[Cd(L)(phen)2]_(n)(6)were synthesized by reactions of dicarboxylate ligand 2,2'-(1,2-phenylenebis(methylene))bis(sulfanediyl)dinobutyric acid(H_(2)L)and 1,10-phenanthroline(phen)with the corresponding metal salts.Complexes 1-6 have been structurally characterized by single-crystal X-ray diffraction analyses,elemental analysis,IR,thermogravimetric analysis,and powder X-ray diffraction.The structures of 1-6 are 1D chains,which are further connected by hydrogen bonding interac-tions to form 3D supramolecular structures.Among them,1 and 2 are isomorphic with L2-of syn-conformation,while L2-shows anti-conformation in 3-6.In addition,the solid-state photoluminescence property of 4-6 was investigated.展开更多
Stimulus-responsive room-temperature phosphorescence(RTP)materials have gained significant attention for their important optoelectronic application prospects.However,the fabrication strategy and underlying mechanism o...Stimulus-responsive room-temperature phosphorescence(RTP)materials have gained significant attention for their important optoelectronic application prospects.However,the fabrication strategy and underlying mechanism of stimulus-responsive RTP materials remain less explored.Herein,we present a reliable strategy for achieving pH-responsive RTP materials by integrating poly(vinyl alcohol)(PVA)with carboxylic acid or amino group functionalized terpyridine(Tpy)derivatives.The resulting Tpy derivativesbased RTP materials displayed reversible changes in emission color,intensity,and lifetime of both prompt and delayed emission.Notably,the RTP emission undergoes a significant diminish upon exposure to acid due to the protonation of Tpy units.Taking advantage of the decent RTP emission and pH-responsiveness of these RTP films,a spatial-time-resolved anti-counterfeiting application is demonstrated as a proof-ofconcept for largely enhancing the security level.This study not only provides new prospects for developing smart RTP materials but also promotes the advancement of optical anti-counterfeiting applications.展开更多
The high throughput prediction of the thermodynamic phase behavior of active pharmaceutical ingredients(APIs)with pharmaceutically relevant excipients remains a major scientific challenge in the screening of pharmaceu...The high throughput prediction of the thermodynamic phase behavior of active pharmaceutical ingredients(APIs)with pharmaceutically relevant excipients remains a major scientific challenge in the screening of pharmaceutical formulations.In this work,a developed machine-learning model efficiently predicts the solubility of APIs in polymers by learning the phase equilibrium principle and using a few molecular descriptors.Under the few-shot learning framework,thermodynamic theory(perturbed-chain statistical associating fluid theory)was used for data augmentation,and computational chemistry was applied for molecular descriptors'screening.The results showed that the developed machine-learning model can predict the API-polymer phase diagram accurately,broaden the solubility data of APIs in polymers,and reproduce the relationship between API solubility and the interaction mechanisms between API and polymer successfully,which provided efficient guidance for the development of pharmaceutical formulations.展开更多
In this work,amido-graphene oxide(GO-NH_(2))loaded chitosan(CTS)composite material(CTS/GO-NH_(2))that acts as both the triboelectric and sensing film was prepared on rotary fan-shaped triboelectric nanogenerator for h...In this work,amido-graphene oxide(GO-NH_(2))loaded chitosan(CTS)composite material(CTS/GO-NH_(2))that acts as both the triboelectric and sensing film was prepared on rotary fan-shaped triboelectric nanogenerator for humidity detection.Compared with the pristine CTSbased triboelectric humidity sensor(CTS-THS)and GONH_(2)-THS,the CTS/GO-NH_(2)-based humidity sensor exhibited higher humidity response and better linearity in the relative humidity(RH)range of 18.7%RH-91.5%RH.The above results can be explained by the massive exposed and less concealed hydrophilic functional groups of CTS with the help of the wrinkle structure of GO-NH_(2).Meanwhile,the CTS/GO-NH_(2)-THS possessed good repeatability and acceptable hysteresis(~6.2%RH).Finally,a humidity sensing mechanism coupling triboelectric contact charging effect with electrons transfer principle under moisture environment was established to interpret the enhanced humidity sensing performance of the composite film-based THS.This work demonstrates that CTS/GONH_(2) composite film can be utilized to fabricate humidity sensors based on the triboelectric effect.展开更多
Monodisperse hollow polymer microspheres having various functional groups on the shell-layer, such as carboxylic acid, pyridyl and amide, were prepared by two-stage distillation precipitation polymerization in neat ac...Monodisperse hollow polymer microspheres having various functional groups on the shell-layer, such as carboxylic acid, pyridyl and amide, were prepared by two-stage distillation precipitation polymerization in neat acetonitrile in the absence of any stabilizer or additive, during which monodisperse poly（methacrylic acid） （PMAA） afforded from the first-stage polymerization was utilized as the seeds for the second-stage polymerization. The shell layer with different functional groups was formed during the second-stage copolymerization of either divinylbenzene （DVB） or ethyleneglycol dimethacrylate （EGDMA） as crosslinker and the functional comonomers, in which the hydrogen-bonding interaction between the carboxylic acid group of PMAA core and the functional groups of the corresponding comonomers, including carboxylic acid, amide and pyridyl, played an essential role for the formation of monodisperse core-shell functional microspheres. The hollow polymer microspheres were then developed after the subsequent removal of PMAA cores by dissolution in ethanol under basic condition. Transmission electron microscopy （TEM） and scanning electron microscopy （SEM） were used to determine the morphology of the resultant PMAA core, functional core-shell microspheres and the corresponding hollow polymer microspheres with different functional groups. FT-IR spectra confirmed the successful incorporation of the various functional groups on the shell layer of the hollow polymer microspheres.展开更多
Steady-state absorption and fluorescence spectra, and time-resolved fluorescence spectra of coumarin 343 （C343） were measured in different solvents. The effect of the solvent on the spectral properties and dipole mo...Steady-state absorption and fluorescence spectra, and time-resolved fluorescence spectra of coumarin 343 （C343） were measured in different solvents. The effect of the solvent on the spectral properties and dipole moment of the lowest excited state of C343 were investigated. It was found that the absorption and fluorescence spectra red-shifted slightly and strongly with increasing solvent polarity, respectively, because the charge distribution of the excited state leaded to the increasing difference between the absorption and fluorescence spectra with increasing solvent polarity. The dipole moment of the lowest excited state of C343 was determined from solvatochromic measurements and the quantum chemical calculation, and the results obtained from these two methods were fully consistent. Investigations of the time-resolved fluorescence of C343 in different solvents indicated that the fluorescence lifetimes increased nearly linearly with 4.45 ns in water. This can be ascribed between C343 and hydrogen donating increasing solvent polarity from 3.09 ns in toluene to to the intermolecular hydrogen bonding interactions solvents展开更多
The reactions of SbCl3 and HgCl2 with 2-（3-pyridyl）benzimidazole （PyBIm） in solution acidified with HCl have been investigated. The PyBIm ligands are protonated into 2-（3-pyridinio）benzimidazolium （H2PyBIm） ca...The reactions of SbCl3 and HgCl2 with 2-（3-pyridyl）benzimidazole （PyBIm） in solution acidified with HCl have been investigated. The PyBIm ligands are protonated into 2-（3-pyridinio）benzimidazolium （H2PyBIm） cations and the corresponding metal ions are bonded with chloride atoms into coordination anions, forming two new coordination compounds, namely, （H2PyBIm）（SbCl5） 1 and （H2PyBIm）2（Hg2Cl8） 2. Both compounds were characterized by X-ray crystallography. Crystal data for 1： triclinic, space group P1^- with a = 5.7030（7）, b = 9.0625（11）, c = 16.5929（18） A, α = 91.808（7）°, β = 93.234（6）, γ = 99.216（7）°, C12H11N3SbCl5, Mr = 496.24, V = 844.44（17） A^3, Z = 2, Dc = 1.952 g/cm^3, μ（MoKα） = 2.419 mm^-1, F（000） = 480, the final R = 0.0496 and wR = 0.1382 for 3433 observed reflections （I 〉 2σ（I））. Crystal data for 2： monoclinic, space group P21/c with a = 7.8061（5）, b = 15.8127（9）, c = 12.2435（9） , β = 91.955（4）o, C24H22N6Hg2Cl8, Mr = 1079.26, V = 1510.40（17） 3, Z = 2, Dc = 2.373 g/cm3, μ（MoKα） = 10.889 mm-1, F（000） = 1008, the final R = 0.0293 and wR = 0.0562 for 2854 observed reflections （I 〉 2σ（I））. X-ray diffraction analysis reveals that the antimony（III） is five-coordinated, exhibiting a slightly distorted square-pyramidal coordination geometry; while in 2, a dimeric [Hg2Cl8]^4-anion consists of two trigonal bipyramids sharing two common edges. The organic cations and coordination anions are connected into a one-dimensional belt and a two-dimensional sheet through N-H···Cl hydrogen bonding interactions in compounds 1 and 2, respectively; both are further aggregated into 3D frameworks by strong π-π contacts.展开更多
The title complex, [Cd（MeHbibzim）（1,4-bdc）]n （1, MelToibzim = 1-methyl-2,2＇- bibenzimidazole, 1,4-bdc = terephthalate）, was synthesized with hydrothermal reactions. The compound crystallizes in monoclinic, spac...The title complex, [Cd（MeHbibzim）（1,4-bdc）]n （1, MelToibzim = 1-methyl-2,2＇- bibenzimidazole, 1,4-bdc = terephthalate）, was synthesized with hydrothermal reactions. The compound crystallizes in monoclinic, space group C2/c with a = 9.822（4）, b = 18.510（7）, c = 22.372（9） A, β = 98.359（6）°, C23H16CdN4O4, Mr = 524.81, V= 4024（3） A3, Z = 8, Dc. = 1.733 g/cm3, μ（MoKa） = 1.126 mm-1, F（000） = 2096, the final R = 0.0597 and wR = 0.1374 for 3906 observed reflections （1 〉 2σ（I））. X-ray diffraction analysis reveals that the Cd atom is coordinated by two nitrogen atoms from the chelating MeHbibzim and three carboxyl oxygen atoms from three terephthalate ligands, thus forming a distorted square pyramidal coordination sphere, [CdN2O3]. Every two Cd atoms are linked together via two carboxyl groups into a dinuclear unit with Cd...Cd separation of 3.806（4） A. The dinuclear building units are linked by terephthalate ligands into two-dimensional layers, which are further aggregated into a 3D framework via hydrogen bonding interactions.展开更多
Two new complexes, [Mn（L）（mmbda）（H_2O）]（1） and [Co（L）（btc）（H_2O）]·H_2O（2）, were synthesized by reacting the corresponding metal（Ⅱ） salts with rigid ligand 1,4-di（1Himidazol-4-yl）benzene（L） ...Two new complexes, [Mn（L）（mmbda）（H_2O）]（1） and [Co（L）（btc）（H_2O）]·H_2O（2）, were synthesized by reacting the corresponding metal（Ⅱ） salts with rigid ligand 1,4-di（1Himidazol-4-yl）benzene（L） and two different carboxylic acids of 5-methylisophthalic acid（H_2mmbda） and 1,2,4-benzenetricarboxylic acid（H_3btc）, respectively. The structures of the complexes were characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and PXRD. Complex 1 crystallizes in triclinic, space group P1 with a = 6.9436（4）, b = 9.7306（6）, c = 15.5302（10） ？, α = 73.7430（10）, β = 85.1010（10）, γ = 70.0360（10）o, V = 946.75（10） ？~3, Z = 2, C_（21）H_（20）N_4O_5 Mn, M_r = 463.33, D_c = 1.618 g/cm^3, μ = 0.742-1, S = 1.002, F（000） = 474, the final R = 0.0285 and wR = 0.0600 for 4328 observed reflections（I 〉 2σ（I））. Complex 2 crystallizes in monoclinic, space group P2_1/n with a = 12.5216（12）, b = 7.3312（8）, c = 22.510（2） ？, β = 93.104（2）o, V = 2063.3（4） ？~3, Z = 4, C_（21）H_（18）N_4O_8Co, M_r = 513.31, D_c = 1.646 g/cm^3, μ = 0.892^（-1） mm, S = 1.096, F（000） = 1044, the final R = 0.0673 and wR = 0.1780 for 3594 observed reflections（I 〉 2σ（I））. Both of complexes are one-dimensional（1D） chain structures and rich hydrogen bonds extend such 1D chains to form three-dimensional（3D） supramolecular polymers.展开更多
The title compound 3-benzyl-6-trichloromethyl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazole I （C11HTC13N4S, Mr = 333.62） has been synthesized, and its structure was determined by elemental analyses, IR, ^1H NMR, ^13C NMR...The title compound 3-benzyl-6-trichloromethyl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazole I （C11HTC13N4S, Mr = 333.62） has been synthesized, and its structure was determined by elemental analyses, IR, ^1H NMR, ^13C NMR, and X-ray diffractions. The crystal is of triclinic, space group P1^-, with a = 5.898（3）, b = 10.510（4）, c = 11.580（5） A, α = 74.936（7）, β= 75.476（7）, γ = 79.647（7）°, V= 665.9（5）/A^3, F（000） = 336, Z= 2, Dc = 1.664 g/cm^3, 2 = 0.71073A, p = 0.834 mm^-1, the final R = 0.0605 and wR = 0.0900. The secondary bonding interactions （SBIs） S…N and π-π stacking interactions are found in the crystal structure and they link the molecules into a three-dimensional network.展开更多
基金This work is supported by the National Natural Science Foundation of China （No.20673105）.
文摘Does the halogen bonding interaction co-exist in liquid when it competes with the hydrogen bonding interaction？ The classical molecular dynamics simulations for the solvation properties of CLF molecule in water are performed with the Lennard-Jones plus Coulomb electrostatic potential parameters that are optimized with ab initio interaction energy calculations for the pre-reactive H2O-CLF complex. We find that the halogen bonding interactions occur between O and CL atoms and have the comparable strength and population with respect to the hydrogen bonding interactions of C1...H.
基金supported by the National Natural Science Foundation of China(Nos.21171040 and 21302019)
文摘A new complex, [Ni2（L）4（H2O）8]（1, L1 = 4-（1H-imidazol-4-yl）benzoic acid）, has been hydrothermally prepared and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and PXRD. Complex 1 crystallizes in monoclinic, space group P21/c with α = 22.281（2）, b = 7.3959（7）, c = 24.978（3） ？, β = 90.876（10）, V = 4115.6（7） ？3, Z = 8, C20H22N4O8Ni, Mr = 505.13, Dc = 1.630 g/cm3, μ = 1.001 mm-1, S = 1.080, F（000） = 2096, the final R = 0.452 and wR = 0.1152 for 9380 observed reflections （I 〉 2σ（I））. The result of X-ray diffraction analysis revealed three different kinds of Ni（II） centre mononuclear molecules in the asymmetric unit. The independent mononuclear units are bridged to form a three-dimensional supramolecular polymer by extensive hydrogen bonds and C–H… non-covalent bonding interactions.
基金sponsored by the National Natural Science Foundation of China (Nos. 22308145, 22208140, 22178159, 22078145)Natural Science Foundation of Jiangsu Province (BK20230791)Postgraduate Research Innovation Program of Jiangsu Province (KYCX24_0165)。
文摘Removing H_(2)S and CO_(2)is of great significance for natural gas purification.With excellent gas affinity and tunable structure,ionic liquids(ILs) have been regarded as nontrivial candidates for fabricating polymer-based membranes.Herein,we firstly reported the incorporation of protic ILs (PILs) having ether-rich and carboxylate sites (ECPILs) into poly(ether-block-amide)(Pebax) matrix for efficient separation H_(2)S and CO_(2)from CH_(4).Notably,the optimal permeability of H_(2)S reaches up to 4310 Barrer (40C,0.50 bar) in Pebax/ECPIL membranes,along with H_(2)S/CH_(4)and (H_(2)StCO_(2))/CH_(4)selectivity of 97.7 and 112.3,respectively.These values are increased by 1125%,160.8%and 145.9%compared to those in neat Pebax membrane.Additionally,the solubility and diffusion coefficients of the gases were measured,demonstrating that ECPIL can simultaneously strengthen the dissolution and diffusion of H_(2)S and CO_(2),thus elevating the permeability and permselectivity.By using quantum chemical calculations and FT-IR spectroscopy,the highly reversible multi-site hydrogen bonding interaction between ECPILs and H_(2)S was revealed,which is responsible for the fast permeation of H_(2)S and good selectivity.Furthermore,H_(2)S/CO_(2)/CH_(4)(3/3/94 mol/mol) ternary mixed gas can be efficiently and stably separated by Pebax/ECPIL membrane for at least 100 h.Overall,this work not only illustrates that PILs with ether-rich and carboxylate hydrogen bonding sites are outstanding materials for simultaneous removal of H_(2)S and CO_(2),but may also provide a novel insight into the design of membrane materials for natural gas upgrading.
基金This work was supported by research grant from the Open Laboratory of Staticaland Dynamical Structure(China)the National Institutes of Health(GM 37453,USA)
文摘Hydrogen bonding interaction in hydrogen fluoride dimer has been investigated by quan- tum-chemical calculation with 6-311G^(**) basis set at various mutual orientations.Atomic charges and charge transfer have been calculated by means of potential-derived method,and decomposition of hydro- gen bonding interaction has been executed.The calculation results show that there is a variation range for the energy-stable orientations,the charge transfer in the range presents maximum value,and the charge transfer interaction plays a decisive role in the hydrogen bonding.
文摘Four micro states of Fe-CO with 3d(sigma)-4s and 3d(delta)-3d(delta) electrons spin-paired or unpaired are examined to investigate the influence of pairing versus unpairing mechanism upon the bondings and interactions in Fe-CO. The calculation results show that the Fe-CO bondings and interactions are determined by a balance between the bonding stabilization and the exchange stabilization with or without 3d(sigma)-4s electron spin-pairing. The 3d(delta)-3d(delta) electron spin-pairing versus unpairing has a surprising large effect on the Fe-CO bonding properties, even though the 3d(delta) orbitals are usually considered as being nonbonding.
基金supported by the National Natural Science Foundation of China(Grant no.52463025,and 52062035)the Major Discipline Academic and Technical Leaders Training Program of Jiangxi Province(Grant no.20213BCJ22056)+2 种基金the Key R&D Program of Jiangxi Province(Grant no.20223BBE51028)the Jiangxi Province Key Laboratory of Lithium-ion Battery Materials and Application(2024SSY05202)the Jiangxi Province Graduate Innovation Special Fund Project(YC2023-B004)。
文摘Oxygen release from Ni-rich cathode is one of the major structural degradations resulting in rapid performance fading in lithium-ion batteries(LIBs).The energy gap between the transition metals(TM)-d band and the O-p band serves as an effective evaluation metric in characterizing the potential for oxygen release.Given that the primary oxidation factors of NCM811 materials vary at different states of charge(SOC),this study employs high-throughput density functional theory(DFT)calculations combined with machine learning(ML)to systematically investigate the regulation mechanism of heteroatoms on the energy gap between the TM-d band(TM=Ni,Co)and O-p band at various SOC levels.Highthroughput DFT calculations were used to study doping thermodynamic stability and complete the database.The results indicate that dopant atoms remain at their original sites even at 50%SOC.Correlation analysis reveals that at 0 SOC,the dopant reduces Ni-O bonding interactions by forming its own bonds with oxygen,thereby preventing lattice oxygen escape and weakening the oxygen binding of the system during Ni redox.At 50%SOC,the dopant and Co atoms synergistically strengthen their bonding interactions with oxygen,thereby maintaining structural stability and inhibiting lattice oxygen escape.Based on R^(2)and root-mean-square error(RMSE),the gradient boosting regression(GBR)algorithm is identified as optimal for predicting the energy gaps between the Ni-d band and O-p band,as well as between the Co-d band and O-p band.Feature importance analysis demonstrates that the magnetic moment(Dma)of the doped atom significantly contributes to the prediction of ΔNi-O and ΔCo-O.In this study,the energy gap regulation mechanisms of Ni-d/O-p and Co-d/O-p are systematically investigated using non-empirical first principle calculations combined with data-driven machine learning,aiming to provide insights into the electrochemical stability of NCM811 and related materials.
基金the National Natural Science Foundation of China(No.21973105)the National Key R&D Program of China(No.2020YFC1910301).
文摘According to the Kamlet-Abraham-Taft(KAT)polarity parameters(α,β,π*),polymers and solvents can be categorized as hydrogen-bond(H-bond)acidic(α>β)or H-bond basic(α<β).Recently,we proposed a quantitative hydrogen bonding(QHB)analysis to predict the solubility of polymers in ionic liquids(ILs)using the product ofΔαΔβ<0 as an indicator,whereΔαis the difference between the H-bond acidic parameters of the polymer and IL,andΔβis the difference in their basicity,while the prerequisite of the“complementary”principle(i.e.,that one component is H-bond acidic and the other is basic)is satisfied.Here,the applicability of QHB analysis was first confirmed by testing the solubilities of carefully chosen polymer/deep eutectic solvent(DES)pairs,as the DESs were eutectic mixtures dominated by hydrogen bonding interactions.Then,our attention focused on the solubility of cellulose in DESs.Our testing results as well as the typical published results were summarized,which indicate that the potential DESs for cellulose dissolution and regeneration must be of the H-bond basic type because the“complementary”principle should be satisfied as a prerequisite.However,the H-bond basic DESs investigated in this study do not show the superior solubility of cellulose that has been commonly observed for H-bond basic ILs,even if the criterion ofΔαΔβ<0 is satisfied for both DESs and ILs.Possible reasons for this discrepancy are given to understand the varying effectiveness in cellulose dissolution for H-bond basic DESs and ILs.
基金financially supported by the materials project (No.104)。
文摘The crystallization behavior of polyamide 6,6(PA66) under complex flow field is of great importance for its final mechanical properties.Poly(vinyl pyrrolidone)(PVP) was applied as crystallization modifying agency to improve processability of PA66.The regulation nature on hydrogen bonds(H-bonds) interaction of PVP was studied upon cooling process.As revealed by in situ FTIR,the sample with 5 wt% PVP displays decreased enthalpy change(ΔH) for both the generation of H-bonds and the transition of H-bonds from “disordered” to “ordered” state,which illustrates the molecular mechanism for the regulation of crystallzation behavior.Moveover,2D-WAXD is applied to reveal the evolution of microstructure for sample under external injection field.Hermans orientation factor(f_(H)) decreases obviously with the addition of PVP,because the relaxation of chain segments is promoted as well the crystallization is retarded.The above crystallization and microstructure changes during the processing provokes the improvement of processability without the apparent sacrifice of mechanical properties.
文摘The through--space and through--bond interactions in 1, 5 -- Cyclooctadiyne are studied. It is shown, with the assistance of improved MS--X_α method, that the through- space interactions decrease with the distance of the orbitals, and both through--space and through--bond interactions of 1, 5- Cyclooctadiyne are sizable but those two interactions oppose each other causing the net splitting to be small for π_z orbital. The calculated ionization potentials are in good agreement with the experiment of photoelectron spectra.
文摘A series of soy protein isolate(SPI)films plasticized by glycerol(Gly)were studied using attenuated total reflectance-Fourier transform infrared spectroscopy(ATR/FTIR).Perturbation-correlation movingwindow two-dimensional(PCMW2D)and two-dimensional correlation(2DCOS)analyses were applied to the amideⅠband and thus the hydrogen bond interaction between SPI and Gly was systematically investigated.When Gly concentrations were in the range 0~35%,the hydrogen bond amongβ-sheets was replaced by the one between SPI chain and Gly molecule,which caused these protein chains being changed toα-helix.However,the transformation ofβ-sheet toα-helix was saturated and both of them tend to change to random coil when Gly concentrations were in the range 35%~60%.
文摘Under solvothermal conditions,six new coordination polymers(CPs)[Mn(L)(phen)(H_(2)O)]_(n)(1),[Co(L)(phen)(H_(2)O)]_(n)(2),[Cu(L)(phen)(H_(2)O)]_(n)(3),[Zn_(2)(L)_(2)(phen)2(H_(2)O)]_(n)(4),[Zn(L)(phen)]_(n)(5),and[Cd(L)(phen)2]_(n)(6)were synthesized by reactions of dicarboxylate ligand 2,2'-(1,2-phenylenebis(methylene))bis(sulfanediyl)dinobutyric acid(H_(2)L)and 1,10-phenanthroline(phen)with the corresponding metal salts.Complexes 1-6 have been structurally characterized by single-crystal X-ray diffraction analyses,elemental analysis,IR,thermogravimetric analysis,and powder X-ray diffraction.The structures of 1-6 are 1D chains,which are further connected by hydrogen bonding interac-tions to form 3D supramolecular structures.Among them,1 and 2 are isomorphic with L2-of syn-conformation,while L2-shows anti-conformation in 3-6.In addition,the solid-state photoluminescence property of 4-6 was investigated.
基金financially supported by the National Natural Science Foundation of China(No.22205249)Zhejiang Provincial Natural Science Foundation of China(No.LQ23B040002)+2 种基金the Sino-German Mobility Program(No.M-0424)Ningbo International Cooperation Project(No.2023H019)China Postdoctoral Science Foundation(Nos.2021TQ0341,2022M723252)。
文摘Stimulus-responsive room-temperature phosphorescence(RTP)materials have gained significant attention for their important optoelectronic application prospects.However,the fabrication strategy and underlying mechanism of stimulus-responsive RTP materials remain less explored.Herein,we present a reliable strategy for achieving pH-responsive RTP materials by integrating poly(vinyl alcohol)(PVA)with carboxylic acid or amino group functionalized terpyridine(Tpy)derivatives.The resulting Tpy derivativesbased RTP materials displayed reversible changes in emission color,intensity,and lifetime of both prompt and delayed emission.Notably,the RTP emission undergoes a significant diminish upon exposure to acid due to the protonation of Tpy units.Taking advantage of the decent RTP emission and pH-responsiveness of these RTP films,a spatial-time-resolved anti-counterfeiting application is demonstrated as a proof-ofconcept for largely enhancing the security level.This study not only provides new prospects for developing smart RTP materials but also promotes the advancement of optical anti-counterfeiting applications.
基金the financial support from the National Natural Science Foundation of China(22278070,21978047,21776046)。
文摘The high throughput prediction of the thermodynamic phase behavior of active pharmaceutical ingredients(APIs)with pharmaceutically relevant excipients remains a major scientific challenge in the screening of pharmaceutical formulations.In this work,a developed machine-learning model efficiently predicts the solubility of APIs in polymers by learning the phase equilibrium principle and using a few molecular descriptors.Under the few-shot learning framework,thermodynamic theory(perturbed-chain statistical associating fluid theory)was used for data augmentation,and computational chemistry was applied for molecular descriptors'screening.The results showed that the developed machine-learning model can predict the API-polymer phase diagram accurately,broaden the solubility data of APIs in polymers,and reproduce the relationship between API solubility and the interaction mechanisms between API and polymer successfully,which provided efficient guidance for the development of pharmaceutical formulations.
基金financially supported by the Natural Science Foundation of China(No.U19A2070)the National Science Funds for Excellent Young Scholars of China(No.61822106)the National Science Funds for Creative Research Groups of China(No.61421002)。
文摘In this work,amido-graphene oxide(GO-NH_(2))loaded chitosan(CTS)composite material(CTS/GO-NH_(2))that acts as both the triboelectric and sensing film was prepared on rotary fan-shaped triboelectric nanogenerator for humidity detection.Compared with the pristine CTSbased triboelectric humidity sensor(CTS-THS)and GONH_(2)-THS,the CTS/GO-NH_(2)-based humidity sensor exhibited higher humidity response and better linearity in the relative humidity(RH)range of 18.7%RH-91.5%RH.The above results can be explained by the massive exposed and less concealed hydrophilic functional groups of CTS with the help of the wrinkle structure of GO-NH_(2).Meanwhile,the CTS/GO-NH_(2)-THS possessed good repeatability and acceptable hysteresis(~6.2%RH).Finally,a humidity sensing mechanism coupling triboelectric contact charging effect with electrons transfer principle under moisture environment was established to interpret the enhanced humidity sensing performance of the composite film-based THS.This work demonstrates that CTS/GONH_(2) composite film can be utilized to fabricate humidity sensors based on the triboelectric effect.
基金supported by the National Natural Science Foundation of China(No.20874049)
文摘Monodisperse hollow polymer microspheres having various functional groups on the shell-layer, such as carboxylic acid, pyridyl and amide, were prepared by two-stage distillation precipitation polymerization in neat acetonitrile in the absence of any stabilizer or additive, during which monodisperse poly（methacrylic acid） （PMAA） afforded from the first-stage polymerization was utilized as the seeds for the second-stage polymerization. The shell layer with different functional groups was formed during the second-stage copolymerization of either divinylbenzene （DVB） or ethyleneglycol dimethacrylate （EGDMA） as crosslinker and the functional comonomers, in which the hydrogen-bonding interaction between the carboxylic acid group of PMAA core and the functional groups of the corresponding comonomers, including carboxylic acid, amide and pyridyl, played an essential role for the formation of monodisperse core-shell functional microspheres. The hollow polymer microspheres were then developed after the subsequent removal of PMAA cores by dissolution in ethanol under basic condition. Transmission electron microscopy （TEM） and scanning electron microscopy （SEM） were used to determine the morphology of the resultant PMAA core, functional core-shell microspheres and the corresponding hollow polymer microspheres with different functional groups. FT-IR spectra confirmed the successful incorporation of the various functional groups on the shell layer of the hollow polymer microspheres.
文摘Steady-state absorption and fluorescence spectra, and time-resolved fluorescence spectra of coumarin 343 （C343） were measured in different solvents. The effect of the solvent on the spectral properties and dipole moment of the lowest excited state of C343 were investigated. It was found that the absorption and fluorescence spectra red-shifted slightly and strongly with increasing solvent polarity, respectively, because the charge distribution of the excited state leaded to the increasing difference between the absorption and fluorescence spectra with increasing solvent polarity. The dipole moment of the lowest excited state of C343 was determined from solvatochromic measurements and the quantum chemical calculation, and the results obtained from these two methods were fully consistent. Investigations of the time-resolved fluorescence of C343 in different solvents indicated that the fluorescence lifetimes increased nearly linearly with 4.45 ns in water. This can be ascribed between C343 and hydrogen donating increasing solvent polarity from 3.09 ns in toluene to to the intermolecular hydrogen bonding interactions solvents
基金supported by the Natural Science Foundation of Fujian Province (2007HZ0001-1, 2009HZ0004-1, 2009HZ0006-1 and 2006L2005)
文摘The reactions of SbCl3 and HgCl2 with 2-（3-pyridyl）benzimidazole （PyBIm） in solution acidified with HCl have been investigated. The PyBIm ligands are protonated into 2-（3-pyridinio）benzimidazolium （H2PyBIm） cations and the corresponding metal ions are bonded with chloride atoms into coordination anions, forming two new coordination compounds, namely, （H2PyBIm）（SbCl5） 1 and （H2PyBIm）2（Hg2Cl8） 2. Both compounds were characterized by X-ray crystallography. Crystal data for 1： triclinic, space group P1^- with a = 5.7030（7）, b = 9.0625（11）, c = 16.5929（18） A, α = 91.808（7）°, β = 93.234（6）, γ = 99.216（7）°, C12H11N3SbCl5, Mr = 496.24, V = 844.44（17） A^3, Z = 2, Dc = 1.952 g/cm^3, μ（MoKα） = 2.419 mm^-1, F（000） = 480, the final R = 0.0496 and wR = 0.1382 for 3433 observed reflections （I 〉 2σ（I））. Crystal data for 2： monoclinic, space group P21/c with a = 7.8061（5）, b = 15.8127（9）, c = 12.2435（9） , β = 91.955（4）o, C24H22N6Hg2Cl8, Mr = 1079.26, V = 1510.40（17） 3, Z = 2, Dc = 2.373 g/cm3, μ（MoKα） = 10.889 mm-1, F（000） = 1008, the final R = 0.0293 and wR = 0.0562 for 2854 observed reflections （I 〉 2σ（I））. X-ray diffraction analysis reveals that the antimony（III） is five-coordinated, exhibiting a slightly distorted square-pyramidal coordination geometry; while in 2, a dimeric [Hg2Cl8]^4-anion consists of two trigonal bipyramids sharing two common edges. The organic cations and coordination anions are connected into a one-dimensional belt and a two-dimensional sheet through N-H···Cl hydrogen bonding interactions in compounds 1 and 2, respectively; both are further aggregated into 3D frameworks by strong π-π contacts.
基金supported by the 973 key program of the MOST(2010CB933501,2012CB821705)the Chinese Academy of Sciences(KJCX2-YW-319,KJCX2-EW-H01)+1 种基金the National Natural Science Foundation of Chinathe Natural Science Foundation of Fujian Province(2007HZ0001-1,2009HZ0004-1,2009HZ0005-1,2009HZ0006-1,2006L2005)
文摘The title complex, [Cd（MeHbibzim）（1,4-bdc）]n （1, MelToibzim = 1-methyl-2,2＇- bibenzimidazole, 1,4-bdc = terephthalate）, was synthesized with hydrothermal reactions. The compound crystallizes in monoclinic, space group C2/c with a = 9.822（4）, b = 18.510（7）, c = 22.372（9） A, β = 98.359（6）°, C23H16CdN4O4, Mr = 524.81, V= 4024（3） A3, Z = 8, Dc. = 1.733 g/cm3, μ（MoKa） = 1.126 mm-1, F（000） = 2096, the final R = 0.0597 and wR = 0.1374 for 3906 observed reflections （1 〉 2σ（I））. X-ray diffraction analysis reveals that the Cd atom is coordinated by two nitrogen atoms from the chelating MeHbibzim and three carboxyl oxygen atoms from three terephthalate ligands, thus forming a distorted square pyramidal coordination sphere, [CdN2O3]. Every two Cd atoms are linked together via two carboxyl groups into a dinuclear unit with Cd...Cd separation of 3.806（4） A. The dinuclear building units are linked by terephthalate ligands into two-dimensional layers, which are further aggregated into a 3D framework via hydrogen bonding interactions.
基金supported by the National Natural Science Foundation of China(No.21171040)excellent organic teaching and research project(No.2013JCJS01)National Undergraduates Innovation Project(201510371010)
文摘Two new complexes, [Mn（L）（mmbda）（H_2O）]（1） and [Co（L）（btc）（H_2O）]·H_2O（2）, were synthesized by reacting the corresponding metal（Ⅱ） salts with rigid ligand 1,4-di（1Himidazol-4-yl）benzene（L） and two different carboxylic acids of 5-methylisophthalic acid（H_2mmbda） and 1,2,4-benzenetricarboxylic acid（H_3btc）, respectively. The structures of the complexes were characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and PXRD. Complex 1 crystallizes in triclinic, space group P1 with a = 6.9436（4）, b = 9.7306（6）, c = 15.5302（10） ？, α = 73.7430（10）, β = 85.1010（10）, γ = 70.0360（10）o, V = 946.75（10） ？~3, Z = 2, C_（21）H_（20）N_4O_5 Mn, M_r = 463.33, D_c = 1.618 g/cm^3, μ = 0.742-1, S = 1.002, F（000） = 474, the final R = 0.0285 and wR = 0.0600 for 4328 observed reflections（I 〉 2σ（I））. Complex 2 crystallizes in monoclinic, space group P2_1/n with a = 12.5216（12）, b = 7.3312（8）, c = 22.510（2） ？, β = 93.104（2）o, V = 2063.3（4） ？~3, Z = 4, C_（21）H_（18）N_4O_8Co, M_r = 513.31, D_c = 1.646 g/cm^3, μ = 0.892^（-1） mm, S = 1.096, F（000） = 1044, the final R = 0.0673 and wR = 0.1780 for 3594 observed reflections（I 〉 2σ（I））. Both of complexes are one-dimensional（1D） chain structures and rich hydrogen bonds extend such 1D chains to form three-dimensional（3D） supramolecular polymers.
基金supported by the Natural Science Foundation of Zhejiang Province (No. M203149)
文摘The title compound 3-benzyl-6-trichloromethyl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazole I （C11HTC13N4S, Mr = 333.62） has been synthesized, and its structure was determined by elemental analyses, IR, ^1H NMR, ^13C NMR, and X-ray diffractions. The crystal is of triclinic, space group P1^-, with a = 5.898（3）, b = 10.510（4）, c = 11.580（5） A, α = 74.936（7）, β= 75.476（7）, γ = 79.647（7）°, V= 665.9（5）/A^3, F（000） = 336, Z= 2, Dc = 1.664 g/cm^3, 2 = 0.71073A, p = 0.834 mm^-1, the final R = 0.0605 and wR = 0.0900. The secondary bonding interactions （SBIs） S…N and π-π stacking interactions are found in the crystal structure and they link the molecules into a three-dimensional network.
