CAJ | 학술논문

介绍一种基于价键理论框架的多组态密度泛函理论(MSDFT)，并以氢气(H2)分子解离过程及硝酸( HNO3)分子在水溶液中的质子转移过程为例，阐述了MSDFT方法的有效性。结果表明，对于H2分子的解离过程， MSDFT方法克服了以往单行列式密度泛函理论( DFT)的弊端，可给出正确的解离曲线，同时由于通过组态相互作用引入了静态电子相关的贡献，其计算精度可接近CASPT2水平；对于HNO3分子在水溶液中的质子转移过程， MSDFT方法可直接构建质子转移的透热势能曲线以及相应的非绝热耦合矩阵元，另一方面通过引入离子组态的贡献，可显著提升其计算精度，使其计算结果与精确结果相吻合。
개소일충기우개건이론광가적다조태밀도범함이론(MSDFT)，병이경기(H2)분자해리과정급초산( HNO3)분자재수용액중적질자전이과정위례，천술료MSDFT방법적유효성。결과표명，대우H2분자적해리과정， MSDFT방법극복료이왕단행렬식밀도범함이론( DFT)적폐단，가급출정학적해리곡선，동시유우통과조태상호작용인입료정태전자상관적공헌，기계산정도가접근CASPT2수평；대우HNO3분자재수용액중적질자전이과정， MSDFT방법가직접구건질자전이적투열세능곡선이급상응적비절열우합구진원，령일방면통과인입리자조태적공헌，가현저제승기계산정도，사기계산결과여정학결과상문합。
A multistate density function theory( MSDFT) based on valence bond theory was introduced. As an application, the MSDFT method was illustrated by the bond dissociation of H2 and the proton transfer between HNO3 and a water molecule. In the dissociation of H2 , the MSDFT method yields a correct behavior as the two H atoms stretch to infinity, and gives a potential well in accord with second-order perturbation using complete active space(CASPT2). For the proton transfer process of HNO3, MSDFT can be used to yield both diabatic and adiabatic potential energy curves as a function of the proton transfer reaction coordinate. For the reaction barrier height, the inclusion of an ionic state in a three-state model can significantly improve the accuracy in barrier height in comparison with the high-level results.