Although the many-body expansion(MBE)approach is widely applied to estimate the energy of large systems containing weak interactions,it is inapplicable to calculating the energies of covalent or metal clusters.In this...Although the many-body expansion(MBE)approach is widely applied to estimate the energy of large systems containing weak interactions,it is inapplicable to calculating the energies of covalent or metal clusters.In this work,we propose an interaction manybody expansion(IMBE)to calculate the energy of atomic clusters containing covalent bonds.In this approach,the energy of a system is expressed as the sum of the energy of atoms and the interaction energy between the atom and its surrounding atoms.The IMBE method is first applied to calculate the energies of nitrogen clusters,in which the interatomic interactions are truncated to four-body terms.The results show that the IMBE approach could significantly reduce the energy error for nitrogen clusters compared with the traditional MBE method.The weak size and structure dependence of the IMBE error with respect to DFT calculations indicates the IMBE method has good potential application in estimating energy of large covalent systems.展开更多
The title cluster compound-Cu5(BTA)6(TT-A)4·5DMF was prepared using thenyltrifluoroacetone and benzotriazolate ligands. The crystal structure indicates that a tetrahedral array of Cu(l), Cu(2), Cu(3) and Cu(4) io...The title cluster compound-Cu5(BTA)6(TT-A)4·5DMF was prepared using thenyltrifluoroacetone and benzotriazolate ligands. The crystal structure indicates that a tetrahedral array of Cu(l), Cu(2), Cu(3) and Cu(4) ions surrounding a central Cu(5) ion are held together by bridging tridentate BTA- and terminated by TTA- bond cap. The three nitrogen atoms of a BTA- bond three different copper ions to form a η3-benzotriazolate. The central Cu ion has a distorted octahedral structure and the surrounding Cu ions are 5 coordinated forming distorted tetragonal structures. The distances between the surrounding Cu(Ⅱ) ions and the central Cu(Ⅱ) ion are in the range of 0.3561-0.3755 nm and those between the surrounding Cu(Ⅱ) ions are in the range of 0.5785-0.6301nm.展开更多
Ab initio quantum mechanical method has been applied to nitrogen cages N_ 2n (n=12-18). Full geometry optimization, harmonic vibrational frequency and thermodynamics data for eight structures of nitrogen cages N_ 2n (...Ab initio quantum mechanical method has been applied to nitrogen cages N_ 2n (n=12-18). Full geometry optimization, harmonic vibrational frequency and thermodynamics data for eight structures of nitrogen cages N_ 2n (n=12-18) were performed at the HF/cc-pVDZ level. Cage N_ 24 (D_ 6d ), N_ 24 (O_h), N_ 26 (D_ 6d ), N_ 28 (T_d), N_ 30 (D_ 5h ), N_ 32 (D_ 3d ), N_ 36 (D_ 2d ) and N_ 36 (D_ 6h ) were found to be local minima on the potential energy surfaces. The computational results show that all the bond lengths of the eight structures are close to 0.145 nm and their bond energies E_ N-N are near to the experimental data of N-N single-bond. In addition, the thermochemical data of these nitrogen cages indicated that they are stable. It suggests that they are candidates for high energy density materials.展开更多
The cluster state is an indispensable resource for one-way quantum computing （lWQC）. We propose a practical scheme for constructing cluster states among nuclear spins in nitrogen-vacancy defect centres （NV centres...The cluster state is an indispensable resource for one-way quantum computing （lWQC）. We propose a practical scheme for constructing cluster states among nuclear spins in nitrogen-vacancy defect centres （NV centres） in different diamonds. The entanglement of nuclear spins within an NV centre is made by hyperfine coupling via electron spin, and the entanglement between remote NV centres is accomplished using the parity projection of emitted photons. We discus the possibility to build large-scale nuclear-spin cluster states with diamonds.展开更多
基金supported by the National Natural Science Foundation of China(No.21773297,No.21973108,and No.21921004)supported by the National Natural Science Foundation of China(No.21805258)supported by the National Natural Science Foundation of China(No.21973107)。
文摘Although the many-body expansion(MBE)approach is widely applied to estimate the energy of large systems containing weak interactions,it is inapplicable to calculating the energies of covalent or metal clusters.In this work,we propose an interaction manybody expansion(IMBE)to calculate the energy of atomic clusters containing covalent bonds.In this approach,the energy of a system is expressed as the sum of the energy of atoms and the interaction energy between the atom and its surrounding atoms.The IMBE method is first applied to calculate the energies of nitrogen clusters,in which the interatomic interactions are truncated to four-body terms.The results show that the IMBE approach could significantly reduce the energy error for nitrogen clusters compared with the traditional MBE method.The weak size and structure dependence of the IMBE error with respect to DFT calculations indicates the IMBE method has good potential application in estimating energy of large covalent systems.
基金This work was supported by the Foundation of Tianjin Scientific Commission (Grant No. 003601711).
文摘The title cluster compound-Cu5(BTA)6(TT-A)4·5DMF was prepared using thenyltrifluoroacetone and benzotriazolate ligands. The crystal structure indicates that a tetrahedral array of Cu(l), Cu(2), Cu(3) and Cu(4) ions surrounding a central Cu(5) ion are held together by bridging tridentate BTA- and terminated by TTA- bond cap. The three nitrogen atoms of a BTA- bond three different copper ions to form a η3-benzotriazolate. The central Cu ion has a distorted octahedral structure and the surrounding Cu ions are 5 coordinated forming distorted tetragonal structures. The distances between the surrounding Cu(Ⅱ) ions and the central Cu(Ⅱ) ion are in the range of 0.3561-0.3755 nm and those between the surrounding Cu(Ⅱ) ions are in the range of 0.5785-0.6301nm.
文摘Ab initio quantum mechanical method has been applied to nitrogen cages N_ 2n (n=12-18). Full geometry optimization, harmonic vibrational frequency and thermodynamics data for eight structures of nitrogen cages N_ 2n (n=12-18) were performed at the HF/cc-pVDZ level. Cage N_ 24 (D_ 6d ), N_ 24 (O_h), N_ 26 (D_ 6d ), N_ 28 (T_d), N_ 30 (D_ 5h ), N_ 32 (D_ 3d ), N_ 36 (D_ 2d ) and N_ 36 (D_ 6h ) were found to be local minima on the potential energy surfaces. The computational results show that all the bond lengths of the eight structures are close to 0.145 nm and their bond energies E_ N-N are near to the experimental data of N-N single-bond. In addition, the thermochemical data of these nitrogen cages indicated that they are stable. It suggests that they are candidates for high energy density materials.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.10774042 and 10875039)the Chinese Academy of Sciences and the National Fundamental Research Program of China(Grant No.10974225)
文摘The cluster state is an indispensable resource for one-way quantum computing （lWQC）. We propose a practical scheme for constructing cluster states among nuclear spins in nitrogen-vacancy defect centres （NV centres） in different diamonds. The entanglement of nuclear spins within an NV centre is made by hyperfine coupling via electron spin, and the entanglement between remote NV centres is accomplished using the parity projection of emitted photons. We discus the possibility to build large-scale nuclear-spin cluster states with diamonds.
