On the construction of quasidiabatic state representations of bound adiabatic state potential energy surfaces coupled by accidental conical intersections: incorporation of higher order terms.
On the construction of quasidiabatic state representations of bound adiabatic state potential energy surfaces coupled by accidental conical intersections: incorporation of higher order terms.
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关于通过意外圆锥相交耦合的束缚绝热态势能面的准绝热态表示的构造：合并高阶项。
DOI：
10.1063/1.3523344
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
M. Schuurman
中科院分区：
文献类型：
--
作者：
J. Dillon;D. Yarkony;M. Schuurman
二次电子振动耦合模型是模拟多原子分子强耦合光电子能谱的重要计算工具。然而，最近的工作表明，需要更高阶的条款，与大多数的初步研究集中在分子与所需的简并性。在这项研究中，我们报告了我们的方法的扩展，用于构建完全二次表示的结合电子态耦合的圆锥形交叉点，它允许包含更高的阶项，在这里证明采用四次展开。程序的开发，消除非物理行为的大位移，一个问题可能是一个地方病的非调和扩展。以下工作表示解离电子状态，拉格朗日乘数被用来约束构造的表示，以准确地再现能量，能量梯度，和scinor衍生物耦合在特定的点，或节点，在核坐标空间。本文用三唑基（CH）（2）N（3）的四个最低电子态对该方法进行了系统的研究。
The quadratic vibronic coupling model is an important computational tool for simulating photoelectron spectra involving strongly coupled electronic states in polyatomic molecules. However, recent work has indicated the need for higher order terms, with most of the initial studies focusing on molecules with symmetry-required degeneracies. In this study we report an extension of our approach for constructing fully quadratic representations of bound electronic states coupled by conical intersections, which allows for the inclusion of higher order terms, demonstrated here employing a quartic expansion. Procedures are developed that eliminate unphysical behavior for large displacements, a problem likely to be an endemic to anharmonic expansions. Following work on representing dissociative electronic states, Lagrange multipliers are used to constrain the constructed representation to reproduce exactly the energy, energy gradients, and∕or derivative couplings at specific points, or nodes, in nuclear coordinate space. The approach is illustrated and systematically studied using the four lowest electronic states of triazolyl, (CH)(2)N(3).