He Sheng-Gui, Clouthier Dennis J
Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506-0055, USA.
J Chem Phys. 2005 Jul 1;123(1):014316. doi: 10.1063/1.1938947.
The effective vibronic Hamiltonian for a linear tetra-atomic molecule in a Pi state has been investigated. In addition to the usual vibrational and Renner-Teller coupling terms, the bending mode anharmonicity, spin-orbit coupling, and Fermi resonance interactions have been added to the model. Terms in the Hamiltonian up to the fourth order are given explicitly for molecules of C(infinityupsilon) symmetry and simplifications for symmetric D(infinityh) molecules are discussed. The matrix elements for the HCCS free radical have been obtained and are used to analyze the observed ground-state levels of HCCS and DCCS in a companion paper. The Sears resonance vibronic interaction that couples levels with the selection rules DeltaK=+/-1, DeltaSigma=-/+1, and DeltaP=0 has also been studied and the matrix elements derived. The determinable combinations of signs for the major parameters in the model are discussed.
已对处于π态的线性四原子分子的有效振动电子哈密顿量进行了研究。除了通常的振动和伦纳 - 泰勒耦合项外，弯曲模式非谐性、自旋 - 轨道耦合以及费米共振相互作用也已被添加到该模型中。对于具有C（∞υ）对称性的分子，明确给出了哈密顿量中直至四阶的项，并讨论了对称D（∞h）分子的简化情况。已获得HCCS自由基的矩阵元，并在一篇配套论文中用于分析观测到的HCCS和DCCS的基态能级。还研究了将具有选择规则ΔK = ±1、ΔΣ = - / +1和ΔP = 0的能级耦合起来的西尔斯共振振动电子相互作用，并推导了矩阵元。讨论了该模型中主要参数可确定的符号组合。
