In this paper, the equilibrium geometry, harmonic frequency and dissociation energy of S2^- and S3^- have been calculated at QCISD/6-311++G(3d2f) and B3P86/6-311++G(3d2f) level. The S2^- ground state is of 2II...In this paper, the equilibrium geometry, harmonic frequency and dissociation energy of S2^- and S3^- have been calculated at QCISD/6-311++G(3d2f) and B3P86/6-311++G(3d2f) level. The S2^- ground state is of 2IIg, the S3^- ground state is of 2B1 and S3^- has a bent (C2v) structure with an angle of 115.65° The results are in good agreement with these reported in other literature. For S3^- ion, the vibration frequencies and the force constants have also been calculated. Base on the general principles of microscopic reversibility, the dissociation limits has been deduced. The Murrell-Sorbie potential energy function for S2^- has been derived according to the ab initio data through the least- squares fitting. The force constants and spectroscopic data for S2^- have been calculated, then compared with other theoretical data. The analytical potential energy function of S3^- have been obtained based on the many-body expansion theory. The structure and energy can correctly reappear on the potential surface.展开更多
The comparison between single-point energy scanning (SPES) and geometry optimization (OPT) in determining the equilibrium geometries of c^3∑g^+ and B^1-Пu states of dimer 7Li2 is made at numerous basis sets by ...The comparison between single-point energy scanning (SPES) and geometry optimization (OPT) in determining the equilibrium geometries of c^3∑g^+ and B^1-Пu states of dimer 7Li2 is made at numerous basis sets by using a symmetryadapted-cluster configuration-interaztion (SAC-CI) method in the Gaussian 03 program package. In this paper the difference of the equilibrium geometries obtained by SPES and by OPT is reported. The results obtained by SPES are found to be more reasonable than those obtained by OPT in full active space at the present SAC-CI level of theory. And the conclusion is attained that the cc-PVTZ is a most suitable basis set for these states. The calculated dissociation energies and equilibrium geometries are 0.8818 eV and 0.3090 nm for c^3∑g^+ state, and 0.3668 eV and 0.2932 nm for B^1-Пu state respectively. The potential energy curves are calculated over a wide internuclear distance range from about 2.5α0 to 37α0 and have a least-squares fit into the Murrell-Sorbie function. According to the calculated analytic potential energy functions, the harmonic frequencies (We) and other spectroscopic data (ωeXe, Be and αe) are calculated. Comparison of the theoretical determinations at present work with the experiments and other theories clearly shows that the present work is the most complete effort and thus represents an improvement over previous theoretical results.展开更多
This paper reports that the equilibrium structure of NH2 has been optimized at the QCISD/6-311++G (3df, 3pd) level. The ground-state NH2 has a bent (C2v, X^2B1) structure with an angle of 103.0582°. The geo...This paper reports that the equilibrium structure of NH2 has been optimized at the QCISD/6-311++G (3df, 3pd) level. The ground-state NH2 has a bent (C2v, X^2B1) structure with an angle of 103.0582°. The geometrical structure is in good agreement with the other calculational and experimental results. The harmonic frequencies and the force constants have also been calculated. Based on the group theory and the principle of microscopic reversibility, the dissociation limits of NH2(C2v, X^2B1) have been derived. The potential energy surface of NH2(X^2B1) is reasonable. The contour lines are constructed, the structure and energy of NH2 reappear on the potential energy surface.展开更多
In this work,we review recent progress on the view of potential energy surfaces and molecular dynamics study of water and its related reactions in the last decade or so.Some important gas-phase reactions of water with...In this work,we review recent progress on the view of potential energy surfaces and molecular dynamics study of water and its related reactions in the last decade or so.Some important gas-phase reactions of water with radicals,chemisorbed dissociative dynamics of water on solid surfaces,and statistical mechanics and vibrational spectrum simulations of water from clusters to the condensed phase have been introduced.The recently developed machine learning techniques,such as the neural networks in a combination of permutational invariant polynomials or fundamental invariants,the atomic neural networks framework,the gaussian approximation potentials with the smooth overlap of atomic position kernel,as well as the many-body expansion framework for the construction of highly accurate potential energy surfaces,have also been discussed.Finally,some suggestions have been provided for further improvement of the potential energy surfaces and dynamics methods of water-related systems.展开更多
We theoretically investigate the excited state intramolecular proton transfer(ESIPT) behavior of the novel fluorophore bis-imine derivative molecule HNP which was designed based on the intersection of 1-(hydrazonometh...We theoretically investigate the excited state intramolecular proton transfer(ESIPT) behavior of the novel fluorophore bis-imine derivative molecule HNP which was designed based on the intersection of 1-(hydrazonomethyl)-naphthalene-2-ol and 1-pyrenecarboxaldehyde. Especially, the density functional theory(DFT) and time-dependent density functional theory(TDDFT) methods for HNP monomer are introduced. Moreover, the "our own n-layered integrated molecular orbital and molecular mechanics"(ONIOM) method(TDDFT:universal force field(UFF)) is used to reveal the aggregation-induced emission(AIE) effect on the ESIPT process for HNP in crystal. Our results confirm that the ESIPT process happens upon the photoexcitation for the HNP monomer and HNP in crystal, which is distinctly monitored by the optimized geometric structures and the potential energy curves. In addition, the results of potential energy curves reveal that the ESIPT process in HNP will be promoted by the AIE effect. Furthermore, the highest occupied molecular orbital(HOMO) and lowest unoccupied molecular orbital(LUMO) for the HNP monomer and HNP in crystal have been calculated. The calculation demonstrates that the electron density decrease of proton donor caused by excitation promotes the ESIPT process. In addition, we find that the variation of atomic dipole moment corrected Hirshfeld population(ADCH) charge for proton acceptor induced by the AIE effect facilitates the ESIPT process. The results will be expected to deepen the understanding of ESIPT dynamics for luminophore under the AIE effect and provide insight into future design of high-efficient AIE compounds.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No 10574039),the Key Program of Science and Technology Research of Education Ministry, China (Grant No 206084), Innovation Talents of Institution of Higher Education of Henan Province, China (Grant No 2006KYCX002), the Natural Science Foundation of Education Bureau of Henan Province, China (Grant No 200510476004).
文摘In this paper, the equilibrium geometry, harmonic frequency and dissociation energy of S2^- and S3^- have been calculated at QCISD/6-311++G(3d2f) and B3P86/6-311++G(3d2f) level. The S2^- ground state is of 2IIg, the S3^- ground state is of 2B1 and S3^- has a bent (C2v) structure with an angle of 115.65° The results are in good agreement with these reported in other literature. For S3^- ion, the vibration frequencies and the force constants have also been calculated. Base on the general principles of microscopic reversibility, the dissociation limits has been deduced. The Murrell-Sorbie potential energy function for S2^- has been derived according to the ab initio data through the least- squares fitting. The force constants and spectroscopic data for S2^- have been calculated, then compared with other theoretical data. The analytical potential energy function of S3^- have been obtained based on the many-body expansion theory. The structure and energy can correctly reappear on the potential surface.
基金Project supported by the National Natural Science Foundation of China (Grant No 10574039), the Henan Innovation for University Prominent Research Talents (Grant No 2006KYCX002) and the National Natural Science Foundation of Education Bureau of Henan Province, China (Grant No 2007140015). We heartily thank Professor Zhu Zheng-Hem of Sichuan University for his helpful discussion about the reasonable dissociation stages of these calculations limits during the planning
文摘The comparison between single-point energy scanning (SPES) and geometry optimization (OPT) in determining the equilibrium geometries of c^3∑g^+ and B^1-Пu states of dimer 7Li2 is made at numerous basis sets by using a symmetryadapted-cluster configuration-interaztion (SAC-CI) method in the Gaussian 03 program package. In this paper the difference of the equilibrium geometries obtained by SPES and by OPT is reported. The results obtained by SPES are found to be more reasonable than those obtained by OPT in full active space at the present SAC-CI level of theory. And the conclusion is attained that the cc-PVTZ is a most suitable basis set for these states. The calculated dissociation energies and equilibrium geometries are 0.8818 eV and 0.3090 nm for c^3∑g^+ state, and 0.3668 eV and 0.2932 nm for B^1-Пu state respectively. The potential energy curves are calculated over a wide internuclear distance range from about 2.5α0 to 37α0 and have a least-squares fit into the Murrell-Sorbie function. According to the calculated analytic potential energy functions, the harmonic frequencies (We) and other spectroscopic data (ωeXe, Be and αe) are calculated. Comparison of the theoretical determinations at present work with the experiments and other theories clearly shows that the present work is the most complete effort and thus represents an improvement over previous theoretical results.
基金Project supported by the National Natural Science Foundation of China (Grant Nos 10574039 and 10174019)Henan Innovation Project For University Prominent Research Talents (Grant No HAIPUTT2006KYCX002)the Natural Science Foundation of Education Commission of Henan Province (Grant Nos 2003140028 and 200510476004)
文摘This paper reports that the equilibrium structure of NH2 has been optimized at the QCISD/6-311++G (3df, 3pd) level. The ground-state NH2 has a bent (C2v, X^2B1) structure with an angle of 103.0582°. The geometrical structure is in good agreement with the other calculational and experimental results. The harmonic frequencies and the force constants have also been calculated. Based on the group theory and the principle of microscopic reversibility, the dissociation limits of NH2(C2v, X^2B1) have been derived. The potential energy surface of NH2(X^2B1) is reasonable. The contour lines are constructed, the structure and energy of NH2 reappear on the potential energy surface.
基金supported by Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(No.2021ZR109)the National Natural Science Foundation of China(No.22173104)。
文摘In this work,we review recent progress on the view of potential energy surfaces and molecular dynamics study of water and its related reactions in the last decade or so.Some important gas-phase reactions of water with radicals,chemisorbed dissociative dynamics of water on solid surfaces,and statistical mechanics and vibrational spectrum simulations of water from clusters to the condensed phase have been introduced.The recently developed machine learning techniques,such as the neural networks in a combination of permutational invariant polynomials or fundamental invariants,the atomic neural networks framework,the gaussian approximation potentials with the smooth overlap of atomic position kernel,as well as the many-body expansion framework for the construction of highly accurate potential energy surfaces,have also been discussed.Finally,some suggestions have been provided for further improvement of the potential energy surfaces and dynamics methods of water-related systems.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11574115 and 11704146)
文摘We theoretically investigate the excited state intramolecular proton transfer(ESIPT) behavior of the novel fluorophore bis-imine derivative molecule HNP which was designed based on the intersection of 1-(hydrazonomethyl)-naphthalene-2-ol and 1-pyrenecarboxaldehyde. Especially, the density functional theory(DFT) and time-dependent density functional theory(TDDFT) methods for HNP monomer are introduced. Moreover, the "our own n-layered integrated molecular orbital and molecular mechanics"(ONIOM) method(TDDFT:universal force field(UFF)) is used to reveal the aggregation-induced emission(AIE) effect on the ESIPT process for HNP in crystal. Our results confirm that the ESIPT process happens upon the photoexcitation for the HNP monomer and HNP in crystal, which is distinctly monitored by the optimized geometric structures and the potential energy curves. In addition, the results of potential energy curves reveal that the ESIPT process in HNP will be promoted by the AIE effect. Furthermore, the highest occupied molecular orbital(HOMO) and lowest unoccupied molecular orbital(LUMO) for the HNP monomer and HNP in crystal have been calculated. The calculation demonstrates that the electron density decrease of proton donor caused by excitation promotes the ESIPT process. In addition, we find that the variation of atomic dipole moment corrected Hirshfeld population(ADCH) charge for proton acceptor induced by the AIE effect facilitates the ESIPT process. The results will be expected to deepen the understanding of ESIPT dynamics for luminophore under the AIE effect and provide insight into future design of high-efficient AIE compounds.