As a cluster overlap amplitude,the reduced-width amplitude is an important physical quantity for analyzing clustering in the nucleus depending on specified channels and has been calculated and widely applied in nuclea...As a cluster overlap amplitude,the reduced-width amplitude is an important physical quantity for analyzing clustering in the nucleus depending on specified channels and has been calculated and widely applied in nuclear cluster physics.In this review,we briefly revisit the theoretical framework for calculating the reduced-width amplitude,as well as the outlines of cluster models to obtain microscopic or semi-microscopic cluster wave functions.We also introduce the recent progress related to cluster overlap amplitudes,including the implementation of cross-section estimation and extension to three-body clustering analysis.Comprehensive examples are provided to demonstrate the application of the reduced-width amplitude in analyzing clustering structures.展开更多
To investigate the structural configuration of^(6)He and^(6)Be in a three-cluster system and to highlight dinucleon correlations,we performed a two-cluster overlap amplitude(TCOA)calculation,which is an extension of t...To investigate the structural configuration of^(6)He and^(6)Be in a three-cluster system and to highlight dinucleon correlations,we performed a two-cluster overlap amplitude(TCOA)calculation,which is an extension of the RWA formalism.The total wave functions were obtained using the generator coordinate method with microscopic cluster wave functions.Based on these wave functions,we calculated the overlap amplitudes to extract the relative motion and spatial correlations between clusters.The computed energy spectra showed reasonable agreement with the experimental data,emphasizing the effectiveness of the present framework for investigating dinucleon correlations in light nuclei.Our results revealed the presence of both dinucleon-like and cigar-like configurations in the ground states of^(6)He and^(6)Be,indicating a coexistence of compact and extended cluster structures.Furthermore,the 2_(1)^(+)state of^(6)He revealed a pronounced dineutron structure,with strong spatial correlations between the two valence neutrons.We also performed calculations for the higher-lying 2_(1)^(+)state,which showed a more spatially extended structure and provided potential references for future experimental investigations.These findings demonstrated that the TCOA method served as a powerful tool to explore cluster dynamics and dinucleon features in light,weakly bound nuclear systems.展开更多
We employed random distributions and gradient descent methods for the Generator Coordinate Method(GCM)to identify effective basis wave functions,taking halo nuclei ^(6)He and ^(6)Li as examples.By comparing the ground...We employed random distributions and gradient descent methods for the Generator Coordinate Method(GCM)to identify effective basis wave functions,taking halo nuclei ^(6)He and ^(6)Li as examples.By comparing the ground state(0^(+))energy of ^(6)He and the excited state(0^(+))energy of 6 Li calculated with various random distributions and manually selected generation coordinates,we found that the heavy tail characteristic of the logistic distribution better describes the features of the halo nuclei.Subsequently,the Adam algorithm from machine learning was applied to optimize the basis wave functions,indicating that a limited number of basis wave functions can approximate the converged values.These results offer some empirical insights for selecting basis wave functions and contribute to the broader application of machine learning methods in predicting effective basis wave functions.展开更多
Nuclear deformations are fundamentally important in nuclear physics.We recently developed a multidimensionally constrained relativistic Hartree-Bogoliubov(MDCRHB)model,in which all multipole deformations respecting th...Nuclear deformations are fundamentally important in nuclear physics.We recently developed a multidimensionally constrained relativistic Hartree-Bogoliubov(MDCRHB)model,in which all multipole deformations respecting the V_(4) symmetry can be considered self-consistently.In this work we extend this model by incorporating the angular momentum projection and parity projection to restore the rotational and parity symmetries broken in the mean-field level.This projected MDCRHB(p-MDCRHB)model enables us to connect certain nuclear spectra to exotic intrinsic shapes such as triangles or tetrahedrons.We present the details of the method and an exemplary calculation for ^(12)C.We develop a triangular moment constraint to generate the triangular configurations consisting of three α clusters arranged as an equilateral triangle.The resulting ^(12)C spectra are consistent with that from a triangular rigid rotor for large separations between the α clusters.We also calculate the B(E2)and B(E3)values for low-lying states and find good agreement with the experiments.展开更多
The a＋^2＋ Ne elastic scattering angular distributions at lower incident energies of Eα= 12.7-31.1 Me V have been analyzed by using the a-folding potential based on the α＋^16O structure model of the ^20Ne nucleus....The a＋^2＋ Ne elastic scattering angular distributions at lower incident energies of Eα= 12.7-31.1 Me V have been analyzed by using the a-folding potential based on the α＋^16O structure model of the ^20Ne nucleus. The a-folding potential with a standard Woods-Saxon type imaginary part, can reasonably describe experimental cross sections and the anomalous large angle scattering （ALAS） features. The anomaly of the a＋^20Ne scattering system is further confirmed , in the lower incident energy region.展开更多
We present an analysis of π-^20Ne elastic scattering at intermediate energy basing on the α＋^16O model of the ^20Ne nucleus and in the framework of Glauber multiple scattering theory. Satisfactory agreement with th...We present an analysis of π-^20Ne elastic scattering at intermediate energy basing on the α＋^16O model of the ^20Ne nucleus and in the framework of Glauber multiple scattering theory. Satisfactory agreement with the general features of the experimental data of pion elastic scattering on the neighboring 4N-type nuclei is obtained without any free parameters. Compared with the experimental angular distributions of pion elastic scattering on ^12 C, ^16O, ^24Mg, and ^28Si nuclei, the diffractive patterns and the positions of the dips and peaks in the angular distributions of ^π-^20Ne elastic scattering are reasonably predicted by the calculations.展开更多
Obtaining nanosized,solution-processable molecules and ions with switchable magnetic moments is crucial for the development of storage devices.In this work,two seven-nuclear rhenium cluster complexes Cs_(7)[{Re_(3)S_(...Obtaining nanosized,solution-processable molecules and ions with switchable magnetic moments is crucial for the development of storage devices.In this work,two seven-nuclear rhenium cluster complexes Cs_(7)[{Re_(3)S_(4)(CN)_(9)}{Re_(4)S_(4)}(CN)_(9)]·10H_(2)O(1)and K_(7)[{Re_(3)Se_(4)(CN)_(9)}{Re_(4)Se_(4)}(CN)_(9)]·15H_(2)O(2)were prepared and comprehensively characterized.The obtained clusters with an even number of cluster valence electrons(CVE)are found to consist of triangular and tetrahedral fragments strongly bonded together by bridging inner ligands and constitute a new structural type.Magnetochemical analysis of complexes has revealed the presence of non-magnetic singlet(MS=0)and magnetic doublet(MS=±1)states with a temperature-dependent population.These states,according to DFT calculations,may originate from the zero-field splitted S=1 ground state,which is quite surprising given that clusters with an even number of CVE usually possess low-spin states(S=0)due to the delocalized nature of the frontier molecular orbitals(MOs)and the effective removal of MO degeneracy by Jahn-Teller spatial distortion of the clusters.We have also succeeded in controlling one-electron oxidation of the clusters,which results in an odd number of CVE and drives the compound into a conventional paramagnetic S=1/2 state.展开更多
Two systems of carbonate complexes were constructed by employing a newly prepared Schiff based ligand(H_(2)L;H_(2)L=2-(hydroxyimino)-2-[(3-methoxyl-2-hydroxyphenyl)methylene]hydrazide)and Ln(acac)_(3)·H_(2)O(Haca...Two systems of carbonate complexes were constructed by employing a newly prepared Schiff based ligand(H_(2)L;H_(2)L=2-(hydroxyimino)-2-[(3-methoxyl-2-hydroxyphenyl)methylene]hydrazide)and Ln(acac)_(3)·H_(2)O(Hacac=acetylacetone)in different reaction solutions.展开更多
Calix[n]arenes,a promising family of macrocyclic ligands,have been widely employed in the construction of polynuclear metal clusters.However,their utilization in titanium-oxo clusters(TOCs)is rare,especially in the re...Calix[n]arenes,a promising family of macrocyclic ligands,have been widely employed in the construction of polynuclear metal clusters.However,their utilization in titanium-oxo clusters(TOCs)is rare,especially in the realm of high-nuclearity TOCs.In this study,we employed tert-butylcalix[6]arene(TBC6A)as an organic“functional armor”owing to its molecular flexibility and versatile topologies to successfully synthesize two TBC6A-functionalized TOCs through a solvothermal reaction.These clusters are denoted as[Ti_(4)(μ_(3)-O)_(2)(TBC_(6)A)_(2)(CH_(3)CN)_(2)]·CH_(3)CN(Ti_(4)-TBC6A;TBC6A=tert-butylcalix[6]arene)and[Ti_(28)(μ_(2)-O)_(18)(μ_(3)-O)_(18)(TBC_(6)A)(PA)_(34)(iPrO)_(2)]·4CH3CN(Ti_(28)-TBC6A;PA=propionic acid,iPrOH=isopropanol).Interestingly,the TBC6A ligand exhibits two distinct configurations:a monoconical configuration for Ti_(4)-TBC6A and a biconical configuration for Ti_(28)-TBC6A,which significantly enhances the structural variety of TOCs.Additionally,the incorporation of auxiliary propionic acid ligands further increases the cluster core size from{Ti_(4)}to{Ti_(28)}with a length of 3.55 nm.Ti_(28)-TBC6A represents the largest calixarene-stabilized TOC reported to date.Density functional theory(DFT)calculations reveal a substantial electron transfer effect from the TBC6A ligand to the titanium-oxo core in Ti_(4)-TBC6A and Ti_(28)-TBC6A,attributed to the predesigned multiple coordination sites of TBC6A for chelation with titanium atoms.This phenomenon broadens the light absorption range of the two TOCs to encompass the visible region,resulting in excellent photoelectronic properties.Of note,Ti_(28)-TBC6A exhibits superior catalytic activity and high stability for CO_(2)fixation owing to the presence of more metal catalytic sites and better photoelectric performance.This work not only demonstrates the flexibility and diversity of macrocyclic ligands in constructing TOCs,but also provides an example of calixarene-stabilized high-nuclearity TOCs,contributing to a comprehensive understanding of their interfacial and metal-core structures.展开更多
Great progress has been made in the design and synthesis of high-nuclear lanthanide clusters with impressive structural connections,high stability,and special topologies,but still lack reliable regularity.Herein,a dro...Great progress has been made in the design and synthesis of high-nuclear lanthanide clusters with impressive structural connections,high stability,and special topologies,but still lack reliable regularity.Herein,a drone-shaped lanthanide cluster(1)was obtained by mixing stoichiometric ratios of 2-pyridinecarbohydrazide,2,3,4-trihydroxybenzaldehyde.展开更多
It is highly desirable yet challenging to incorporate open micropores with mass transportation and open active metal sites into metal-organic frameworks(MOFs)for developing novel highly efficient catalysts.Herein,we r...It is highly desirable yet challenging to incorporate open micropores with mass transportation and open active metal sites into metal-organic frameworks(MOFs)for developing novel highly efficient catalysts.Herein,we report a catalyst of low-nuclearity copper-cluster-based micropore MOF,namely H-1e,incor-porated with unsaturated Cu(Ⅱ)centres as open active sites obtained via a highly efficient electrochemical synthesis within 20 minutes.The catalyst H-1e shows potential porosity with 1D open functionalized hexagonal channels for size-selective air oxidation as well as high stability.The electrochemically pre-pared H-1e exhibits excellent catalytic aerobic oxidation activity for the conversion of alcohols(mini-size)to aldehydes with over 99%selectivity and 99%yield under air conditions,showing excellent reusability and stability.The selective catalytic performances are found to be closely dependent on the suitable aperture size of the 1D channels in H-1e,which provided better beds for the oxidation transformations(confirmed by the computational DFT study).In this study,it offers a simple and potential strategy to con-struct microporous materials with open active metal sites to promote the catalytic efficiency of MOFs by electrochemical synthesis.展开更多
The study of cluster structures in light nuclei is extending to the heavy nuclei in these years. As for the stable N = Z nuclei, from the lighter 8Be, 12C nuclei to the heavier 20Ne and even the 40Ca and 44Ti medium n...The study of cluster structures in light nuclei is extending to the heavy nuclei in these years. As for the stable N = Z nuclei, from the lighter 8Be, 12C nuclei to the heavier 20Ne and even the 40Ca and 44Ti medium nuclei, the a cluster structures have been well studied and confirmed. In heavy nuclei, due to the dominated mean field, the existence of α cluster structure is not clear as light nuclei but some clues were found for indicating the core＋ α cluster structure in some nuclei, in particular, the 208 pb＋α structure in 212Po. We review some recent progress about the theoretical and experimental explorations of the a-clustering effects in heavy nuclei. We also discuss the possible a cluster structure of heavy nuclei from the view of a decay.展开更多
Scrupulous theoretical study of 8Be nucleus states,both clustered and non-clustered,is performed over a wide range of excitation energies.The quantities that characterize the degree of the alpha-clustering of these st...Scrupulous theoretical study of 8Be nucleus states,both clustered and non-clustered,is performed over a wide range of excitation energies.The quantities that characterize the degree of the alpha-clustering of these states,i.e.,spectroscopic factors,cluster form factors,and alpha-decay widths,are computed in the framework of the developed accurate ab initio approach.Other basic properties of the 8Be spectrum,including the binding and excitation energies and the mean values of the isospin,are calculated simultaneously.In the majority of instances,the results of the computation turn out to be in good agreement with the spectroscopic data.A number of predictions are made,and corresponding verification experiments are proposed.Prospects of the developed approach for nuclear spectroscopy are demonstrated.展开更多
The paper includes discussions on the important role of neutron and alpha configurations in proton-rich nuclei in nuclear astrophysics in terms of nucleosynthesis under extremely high-temperature hydrogenburning condi...The paper includes discussions on the important role of neutron and alpha configurations in proton-rich nuclei in nuclear astrophysics in terms of nucleosynthesis under extremely high-temperature hydrogenburning conditions. The νp-process, which is supposed to take place at the very early epoch of type II supernovae, has considerable neutrons and alphas together with protons. The alpha-induced reactions on proton-rich unstable nuclei in the light mass regions is expected to play a crucial role, but very few of them were investigated well yet because of the experimental difficulties. Specifically, I report our recent experimental effort for the breakout process from the pp-chain region,~7Be(α, γ)^(11)C(α,p)^(14)N under the νp-process. The neutron-induced reactions on proton-rich nuclei, which is even more a challenging subject, were investigated previously for very few nuclei. One possible experimental method is the Trojan Horse Method(THM). We successfully have applied THM to the ^(18)F(n,α)^(14)N reaction study with an unstable beam of ^(18)F.展开更多
Lanthanide(Ln)high-nuclearity clusters express charming structures and extensive potential applications;nevertheless,the progress of successfully obtaining Ln clusters is still untoward.Herein,two fascinating and clas...Lanthanide(Ln)high-nuclearity clusters express charming structures and extensive potential applications;nevertheless,the progress of successfully obtaining Ln clusters is still untoward.Herein,two fascinating and classical 60-metal configurations were obtained based on mixed-lanthanide and solvothermal conditions,namely[Ln_(60)(CO_(3))8(μ3-OH)_(96)(H_(2)dmp)_(24)(Hdmp)_(12)]Br_(12)(NO_(3))_(8)(CH_(3)OH)_(x)(H_(2)O)_(y)(abbreviated as mixed-Ln_(60);for compound 1,Ln_(60)=Eu_(52.7)Gd_(7.3),x=8,y=43;for compound 2,Ln_(60)=Eu_(52.2)Tb_(7.8),x=15,y=30;H_(2)dmp^(−)or Hdmp^(2−)=2,2-dimethylol propionic acid=L).The crystallographic study showed that the 60-metal core of compounds 1 and 2 are protected by a single type of organic ligand without any extra auxiliary ligand to complete the coordination sphere,which are the first to be reported in the containing Ln high-nuclearity clusters.Besides,the synthesis of 1 and 2 provides a practical way to obtain more analogues of Ln high-nuclearity clusters,featuring the original structure of the metal frame,which is expected to break the ionic radius limitation in the synthesis.展开更多
Two novel compounds based on high-nuclear metal-oxygen clusters,copper-amine complexes and alkaline earth metals were successfully synthesized under hydrothermal conditions,with chemical formulae[Cu(en)_(2)]_(3.5)Ba_(...Two novel compounds based on high-nuclear metal-oxygen clusters,copper-amine complexes and alkaline earth metals were successfully synthesized under hydrothermal conditions,with chemical formulae[Cu(en)_(2)]_(3.5)Ba_(2)[H_(2.5)K_(0.5)SiNb_(18)O_(54)]·18H_(2)O(1)and[Cu(en)_(2)]_(5)Ba_(2)K_(2)[H_(13)K_(2)Nb_(31)O_(93)]·24.5H_(2)O(2)(en=ethylenediamine),respectively.The compounds were characterized by single-crystal X-ray diffraction,infrared spectroscopy(IR),powder X-ray diffraction(PXRD),and ultraviolet-visible spectroscopy(UV-Vis).Interestingly,both compounds exhibit 3D grid structures constructed from high-nuclear polyoxoanions,copper-amine complexes,and alkaline earth metals.Beyond synthesis and structural elucidation,the catalytic performance of these compounds in styrene oxidation was investigated,revealing that the incorporation of barium ions plays a critical role in modulating the conversion and selectivity toward styrene oxide.展开更多
Developing a new strategy for the synthesis of high-nuclear transition metal(TM)cluster substituted polyoxometalates(POMs)provides an avenue for new materials with unique functions.Herein,the synergetic coordination s...Developing a new strategy for the synthesis of high-nuclear transition metal(TM)cluster substituted polyoxometalates(POMs)provides an avenue for new materials with unique functions.Herein,the synergetic coordination strategy of 1,2,4-1H-triazole(Htrz),ethylenediamine(en),and a lacunary POM was applied to construct a highnuclear Ni cluster substituted POM.As a result,a{Ni_(30)}cluster substituted POM,[Ni(trz)3]2@[Ni_(30)(H2O)16]POM.展开更多
The exploration of high-nuclearity molecular molybdenum titanium-oxo clusters(MoTOCs)and their reactivity is a great challenge for polyoxometalate chemistry and materials science.Herein,we report a giant MoTOC[K_(8)(H...The exploration of high-nuclearity molecular molybdenum titanium-oxo clusters(MoTOCs)and their reactivity is a great challenge for polyoxometalate chemistry and materials science.Herein,we report a giant MoTOC[K_(8)(H_(2)O)_(8)][Ti_(12)(O_(2))_(6)(OH)_(12)Mo_(42)O_(124)(O_(2))_(18)(H_(2)O)_(17)]·31H_(2)O(1)by self-assembly of degraded lacunary isopolymolybdate fragments and peroxide-stabilized titanium ions in aqueous solution.Compound 1 features 54 metal centers and a rare pure inorganic triangular prism structure with a size of 1.8×1.8×1.5 nm^(3),which is the first and largest water-soluble MoTOC found to date.More importantly,it contains multiple peroxo groups on the surface,which makes it exhibit superior benzyl alcohol/benzaldehyde(photo)catalytic oxidation performance.This work opens an unusual avenue for the synthesis of giant MoTOCs.展开更多
基金supported by the National Key R&D Program of China(No.2023YFA1606701)the National Natural Science Foundation of China(Nos.12175042 and 12147101)。
文摘As a cluster overlap amplitude,the reduced-width amplitude is an important physical quantity for analyzing clustering in the nucleus depending on specified channels and has been calculated and widely applied in nuclear cluster physics.In this review,we briefly revisit the theoretical framework for calculating the reduced-width amplitude,as well as the outlines of cluster models to obtain microscopic or semi-microscopic cluster wave functions.We also introduce the recent progress related to cluster overlap amplitudes,including the implementation of cross-section estimation and extension to three-body clustering analysis.Comprehensive examples are provided to demonstrate the application of the reduced-width amplitude in analyzing clustering structures.
基金supported by the National Key R&D Program of China(Nos.2023YFA1606701 and 2022YFA1602402)the National Natural Science Foundation of China(Nos.12175042,11890710,11890714,12047514,12147101,and 12347106)+1 种基金Guangdong Major Project of Basic and Applied Basic Research(No.2020B0301030008)the 111 Project。
文摘To investigate the structural configuration of^(6)He and^(6)Be in a three-cluster system and to highlight dinucleon correlations,we performed a two-cluster overlap amplitude(TCOA)calculation,which is an extension of the RWA formalism.The total wave functions were obtained using the generator coordinate method with microscopic cluster wave functions.Based on these wave functions,we calculated the overlap amplitudes to extract the relative motion and spatial correlations between clusters.The computed energy spectra showed reasonable agreement with the experimental data,emphasizing the effectiveness of the present framework for investigating dinucleon correlations in light nuclei.Our results revealed the presence of both dinucleon-like and cigar-like configurations in the ground states of^(6)He and^(6)Be,indicating a coexistence of compact and extended cluster structures.Furthermore,the 2_(1)^(+)state of^(6)He revealed a pronounced dineutron structure,with strong spatial correlations between the two valence neutrons.We also performed calculations for the higher-lying 2_(1)^(+)state,which showed a more spatially extended structure and provided potential references for future experimental investigations.These findings demonstrated that the TCOA method served as a powerful tool to explore cluster dynamics and dinucleon features in light,weakly bound nuclear systems.
基金supported by the National Key R&D Program of China(No.2023YFA1606701)the National Natural Science Foundation of China(Nos.12175042,11890710,11890714,12047514,12147101,and 12347106)+1 种基金Guangdong Major Project of Basic and Applied Basic Research(No.2020B0301030008)China National Key R&D Program(No.2022YFA1602402).
文摘We employed random distributions and gradient descent methods for the Generator Coordinate Method(GCM)to identify effective basis wave functions,taking halo nuclei ^(6)He and ^(6)Li as examples.By comparing the ground state(0^(+))energy of ^(6)He and the excited state(0^(+))energy of 6 Li calculated with various random distributions and manually selected generation coordinates,we found that the heavy tail characteristic of the logistic distribution better describes the features of the halo nuclei.Subsequently,the Adam algorithm from machine learning was applied to optimize the basis wave functions,indicating that a limited number of basis wave functions can approximate the converged values.These results offer some empirical insights for selecting basis wave functions and contribute to the broader application of machine learning methods in predicting effective basis wave functions.
基金This work has been supported by NSAF(Grant No.U1930403)the National Key R&D Program of China(Grant No.2018YFA0404402)+2 种基金the National Natural Science Foundation of China(Grant No.11525524,No.12070131001,No.12047503,and No.11961141004)the Key Research Program of Frontier Sciences of Chinese Academy of Sciences(Grant No.QYZDB-SSWSYS013)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB34010000 and No.XDPB15).
文摘Nuclear deformations are fundamentally important in nuclear physics.We recently developed a multidimensionally constrained relativistic Hartree-Bogoliubov(MDCRHB)model,in which all multipole deformations respecting the V_(4) symmetry can be considered self-consistently.In this work we extend this model by incorporating the angular momentum projection and parity projection to restore the rotational and parity symmetries broken in the mean-field level.This projected MDCRHB(p-MDCRHB)model enables us to connect certain nuclear spectra to exotic intrinsic shapes such as triangles or tetrahedrons.We present the details of the method and an exemplary calculation for ^(12)C.We develop a triangular moment constraint to generate the triangular configurations consisting of three α clusters arranged as an equilateral triangle.The resulting ^(12)C spectra are consistent with that from a triangular rigid rotor for large separations between the α clusters.We also calculate the B(E2)and B(E3)values for low-lying states and find good agreement with the experiments.
基金Supported by National Natural Science Foundation of China under Grant No.10865002
文摘The a＋^2＋ Ne elastic scattering angular distributions at lower incident energies of Eα= 12.7-31.1 Me V have been analyzed by using the a-folding potential based on the α＋^16O structure model of the ^20Ne nucleus. The a-folding potential with a standard Woods-Saxon type imaginary part, can reasonably describe experimental cross sections and the anomalous large angle scattering （ALAS） features. The anomaly of the a＋^20Ne scattering system is further confirmed , in the lower incident energy region.
基金Supported by National Natural Science Foundation of China under Grant No.11265004
文摘We present an analysis of π-^20Ne elastic scattering at intermediate energy basing on the α＋^16O model of the ^20Ne nucleus and in the framework of Glauber multiple scattering theory. Satisfactory agreement with the general features of the experimental data of pion elastic scattering on the neighboring 4N-type nuclei is obtained without any free parameters. Compared with the experimental angular distributions of pion elastic scattering on ^12 C, ^16O, ^24Mg, and ^28Si nuclei, the diffractive patterns and the positions of the dips and peaks in the angular distributions of ^π-^20Ne elastic scattering are reasonably predicted by the calculations.
基金funded by the Russian Science Foundation(project no.23-13-00081).
文摘Obtaining nanosized,solution-processable molecules and ions with switchable magnetic moments is crucial for the development of storage devices.In this work,two seven-nuclear rhenium cluster complexes Cs_(7)[{Re_(3)S_(4)(CN)_(9)}{Re_(4)S_(4)}(CN)_(9)]·10H_(2)O(1)and K_(7)[{Re_(3)Se_(4)(CN)_(9)}{Re_(4)Se_(4)}(CN)_(9)]·15H_(2)O(2)were prepared and comprehensively characterized.The obtained clusters with an even number of cluster valence electrons(CVE)are found to consist of triangular and tetrahedral fragments strongly bonded together by bridging inner ligands and constitute a new structural type.Magnetochemical analysis of complexes has revealed the presence of non-magnetic singlet(MS=0)and magnetic doublet(MS=±1)states with a temperature-dependent population.These states,according to DFT calculations,may originate from the zero-field splitted S=1 ground state,which is quite surprising given that clusters with an even number of CVE usually possess low-spin states(S=0)due to the delocalized nature of the frontier molecular orbitals(MOs)and the effective removal of MO degeneracy by Jahn-Teller spatial distortion of the clusters.We have also succeeded in controlling one-electron oxidation of the clusters,which results in an odd number of CVE and drives the compound into a conventional paramagnetic S=1/2 state.
基金supported by the Natural Science Foundation of China(21701039 and 21473121)the Natural Science Foundation of Hebei Province(B2017201055)the 111 project(B12015)and the Hebei University construction project for comprehensive strength promotion of Midwest colleges and universities.
文摘Two systems of carbonate complexes were constructed by employing a newly prepared Schiff based ligand(H_(2)L;H_(2)L=2-(hydroxyimino)-2-[(3-methoxyl-2-hydroxyphenyl)methylene]hydrazide)and Ln(acac)_(3)·H_(2)O(Hacac=acetylacetone)in different reaction solutions.
基金supported by the National Natural Science Foundation of China(Grant No.22325105,22201159,22171164,91961105,92361301,and 52261135637)the Natural Science Foundation of Shandong Province(No.ZR2021QB077)+1 种基金the Doctoral Program of Liaocheng University(No.318051944)the financial support provided through the Researchers Supporting Project Number(RSP2024R147),King Saud University,Riyadh,Saudi Arabia.
文摘Calix[n]arenes,a promising family of macrocyclic ligands,have been widely employed in the construction of polynuclear metal clusters.However,their utilization in titanium-oxo clusters(TOCs)is rare,especially in the realm of high-nuclearity TOCs.In this study,we employed tert-butylcalix[6]arene(TBC6A)as an organic“functional armor”owing to its molecular flexibility and versatile topologies to successfully synthesize two TBC6A-functionalized TOCs through a solvothermal reaction.These clusters are denoted as[Ti_(4)(μ_(3)-O)_(2)(TBC_(6)A)_(2)(CH_(3)CN)_(2)]·CH_(3)CN(Ti_(4)-TBC6A;TBC6A=tert-butylcalix[6]arene)and[Ti_(28)(μ_(2)-O)_(18)(μ_(3)-O)_(18)(TBC_(6)A)(PA)_(34)(iPrO)_(2)]·4CH3CN(Ti_(28)-TBC6A;PA=propionic acid,iPrOH=isopropanol).Interestingly,the TBC6A ligand exhibits two distinct configurations:a monoconical configuration for Ti_(4)-TBC6A and a biconical configuration for Ti_(28)-TBC6A,which significantly enhances the structural variety of TOCs.Additionally,the incorporation of auxiliary propionic acid ligands further increases the cluster core size from{Ti_(4)}to{Ti_(28)}with a length of 3.55 nm.Ti_(28)-TBC6A represents the largest calixarene-stabilized TOC reported to date.Density functional theory(DFT)calculations reveal a substantial electron transfer effect from the TBC6A ligand to the titanium-oxo core in Ti_(4)-TBC6A and Ti_(28)-TBC6A,attributed to the predesigned multiple coordination sites of TBC6A for chelation with titanium atoms.This phenomenon broadens the light absorption range of the two TOCs to encompass the visible region,resulting in excellent photoelectronic properties.Of note,Ti_(28)-TBC6A exhibits superior catalytic activity and high stability for CO_(2)fixation owing to the presence of more metal catalytic sites and better photoelectric performance.This work not only demonstrates the flexibility and diversity of macrocyclic ligands in constructing TOCs,but also provides an example of calixarene-stabilized high-nuclearity TOCs,contributing to a comprehensive understanding of their interfacial and metal-core structures.
基金supported by the National Natural Science Foundation of China(22271068,22061005,and 22075058)Innovation Project of Guangxi Graduate Education(YCBZ2023059).
文摘Great progress has been made in the design and synthesis of high-nuclear lanthanide clusters with impressive structural connections,high stability,and special topologies,but still lack reliable regularity.Herein,a drone-shaped lanthanide cluster(1)was obtained by mixing stoichiometric ratios of 2-pyridinecarbohydrazide,2,3,4-trihydroxybenzaldehyde.
基金supported by the International Scientific and Technological Cooperation Foundation of Science and Technology Department of Jilin province(No.20200801041GH)Science and Technology Department of Changchun(21ZGM02),P.R.China.
文摘It is highly desirable yet challenging to incorporate open micropores with mass transportation and open active metal sites into metal-organic frameworks(MOFs)for developing novel highly efficient catalysts.Herein,we report a catalyst of low-nuclearity copper-cluster-based micropore MOF,namely H-1e,incor-porated with unsaturated Cu(Ⅱ)centres as open active sites obtained via a highly efficient electrochemical synthesis within 20 minutes.The catalyst H-1e shows potential porosity with 1D open functionalized hexagonal channels for size-selective air oxidation as well as high stability.The electrochemically pre-pared H-1e exhibits excellent catalytic aerobic oxidation activity for the conversion of alcohols(mini-size)to aldehydes with over 99%selectivity and 99%yield under air conditions,showing excellent reusability and stability.The selective catalytic performances are found to be closely dependent on the suitable aperture size of the 1D channels in H-1e,which provided better beds for the oxidation transformations(confirmed by the computational DFT study).In this study,it offers a simple and potential strategy to con-struct microporous materials with open active metal sites to promote the catalytic efficiency of MOFs by electrochemical synthesis.
文摘The study of cluster structures in light nuclei is extending to the heavy nuclei in these years. As for the stable N = Z nuclei, from the lighter 8Be, 12C nuclei to the heavier 20Ne and even the 40Ca and 44Ti medium nuclei, the a cluster structures have been well studied and confirmed. In heavy nuclei, due to the dominated mean field, the existence of α cluster structure is not clear as light nuclei but some clues were found for indicating the core＋ α cluster structure in some nuclei, in particular, the 208 pb＋α structure in 212Po. We review some recent progress about the theoretical and experimental explorations of the a-clustering effects in heavy nuclei. We also discuss the possible a cluster structure of heavy nuclei from the view of a decay.
文摘Scrupulous theoretical study of 8Be nucleus states,both clustered and non-clustered,is performed over a wide range of excitation energies.The quantities that characterize the degree of the alpha-clustering of these states,i.e.,spectroscopic factors,cluster form factors,and alpha-decay widths,are computed in the framework of the developed accurate ab initio approach.Other basic properties of the 8Be spectrum,including the binding and excitation energies and the mean values of the isospin,are calculated simultaneously.In the majority of instances,the results of the computation turn out to be in good agreement with the spectroscopic data.A number of predictions are made,and corresponding verification experiments are proposed.Prospects of the developed approach for nuclear spectroscopy are demonstrated.
基金Japan Society for the Promotion of Science(JSPS)Research(KAKENHI)(26287058)
文摘The paper includes discussions on the important role of neutron and alpha configurations in proton-rich nuclei in nuclear astrophysics in terms of nucleosynthesis under extremely high-temperature hydrogenburning conditions. The νp-process, which is supposed to take place at the very early epoch of type II supernovae, has considerable neutrons and alphas together with protons. The alpha-induced reactions on proton-rich unstable nuclei in the light mass regions is expected to play a crucial role, but very few of them were investigated well yet because of the experimental difficulties. Specifically, I report our recent experimental effort for the breakout process from the pp-chain region,~7Be(α, γ)^(11)C(α,p)^(14)N under the νp-process. The neutron-induced reactions on proton-rich nuclei, which is even more a challenging subject, were investigated previously for very few nuclei. One possible experimental method is the Trojan Horse Method(THM). We successfully have applied THM to the ^(18)F(n,α)^(14)N reaction study with an unstable beam of ^(18)F.
基金supported by NSFC(Grant 21571103)and Natural Science Foundation of Jiangsu Province(Grant BK20191359).
文摘Lanthanide(Ln)high-nuclearity clusters express charming structures and extensive potential applications;nevertheless,the progress of successfully obtaining Ln clusters is still untoward.Herein,two fascinating and classical 60-metal configurations were obtained based on mixed-lanthanide and solvothermal conditions,namely[Ln_(60)(CO_(3))8(μ3-OH)_(96)(H_(2)dmp)_(24)(Hdmp)_(12)]Br_(12)(NO_(3))_(8)(CH_(3)OH)_(x)(H_(2)O)_(y)(abbreviated as mixed-Ln_(60);for compound 1,Ln_(60)=Eu_(52.7)Gd_(7.3),x=8,y=43;for compound 2,Ln_(60)=Eu_(52.2)Tb_(7.8),x=15,y=30;H_(2)dmp^(−)or Hdmp^(2−)=2,2-dimethylol propionic acid=L).The crystallographic study showed that the 60-metal core of compounds 1 and 2 are protected by a single type of organic ligand without any extra auxiliary ligand to complete the coordination sphere,which are the first to be reported in the containing Ln high-nuclearity clusters.Besides,the synthesis of 1 and 2 provides a practical way to obtain more analogues of Ln high-nuclearity clusters,featuring the original structure of the metal frame,which is expected to break the ionic radius limitation in the synthesis.
基金Jilin Provincial Department of science and technology(No.20190802027ZG).
文摘Two novel compounds based on high-nuclear metal-oxygen clusters,copper-amine complexes and alkaline earth metals were successfully synthesized under hydrothermal conditions,with chemical formulae[Cu(en)_(2)]_(3.5)Ba_(2)[H_(2.5)K_(0.5)SiNb_(18)O_(54)]·18H_(2)O(1)and[Cu(en)_(2)]_(5)Ba_(2)K_(2)[H_(13)K_(2)Nb_(31)O_(93)]·24.5H_(2)O(2)(en=ethylenediamine),respectively.The compounds were characterized by single-crystal X-ray diffraction,infrared spectroscopy(IR),powder X-ray diffraction(PXRD),and ultraviolet-visible spectroscopy(UV-Vis).Interestingly,both compounds exhibit 3D grid structures constructed from high-nuclear polyoxoanions,copper-amine complexes,and alkaline earth metals.Beyond synthesis and structural elucidation,the catalytic performance of these compounds in styrene oxidation was investigated,revealing that the incorporation of barium ions plays a critical role in modulating the conversion and selectivity toward styrene oxide.
基金financially supported by the National Natural Science Foundation of China(21773247,21521061,21875252)the Natural Science Foundation of Fujian Province(2006L2005).
文摘Developing a new strategy for the synthesis of high-nuclear transition metal(TM)cluster substituted polyoxometalates(POMs)provides an avenue for new materials with unique functions.Herein,the synergetic coordination strategy of 1,2,4-1H-triazole(Htrz),ethylenediamine(en),and a lacunary POM was applied to construct a highnuclear Ni cluster substituted POM.As a result,a{Ni_(30)}cluster substituted POM,[Ni(trz)3]2@[Ni_(30)(H2O)16]POM.
基金supported by the Program for the Development of Science and Technology of Jilin Province(Item No.YDZJ202201ZYTS395 and YDZJ202201ZYTS313)the National Natural Science Foundation of China(Grant No.22201097 and 21771035).
文摘The exploration of high-nuclearity molecular molybdenum titanium-oxo clusters(MoTOCs)and their reactivity is a great challenge for polyoxometalate chemistry and materials science.Herein,we report a giant MoTOC[K_(8)(H_(2)O)_(8)][Ti_(12)(O_(2))_(6)(OH)_(12)Mo_(42)O_(124)(O_(2))_(18)(H_(2)O)_(17)]·31H_(2)O(1)by self-assembly of degraded lacunary isopolymolybdate fragments and peroxide-stabilized titanium ions in aqueous solution.Compound 1 features 54 metal centers and a rare pure inorganic triangular prism structure with a size of 1.8×1.8×1.5 nm^(3),which is the first and largest water-soluble MoTOC found to date.More importantly,it contains multiple peroxo groups on the surface,which makes it exhibit superior benzyl alcohol/benzaldehyde(photo)catalytic oxidation performance.This work opens an unusual avenue for the synthesis of giant MoTOCs.
