Centre for Theoretical Chemistry and Physics, The New Zealand Institute for Advanced Study, Massey University, 0745 Auckland, New Zealand.
Phys Chem Chem Phys. 2011 Nov 14;13(42):18762-8. doi: 10.1039/c1cp21163c. Epub 2011 Aug 25.
We compare the 3(4)A(1) and 4(4)B(2) states of homonuclear and heteronuclear alkali trimers formed of potassium and rubidium. The Multireference Rayleigh Schrödinger Perturbation Theory of second order is applied to obtain the corresponding adiabatic potential energy surfaces. In the case of homonuclear trimers these pairs of states correspond to the two branches of the E⊗e Jahn-Teller distorted 2(4)E' state. For heteronuclear trimers, the vibrational modes Q(x) and Q(y) are no longer degenerate, but the two electronic states still show a conical intersection at obtuse (KRb(2)) or acute (K(2)Rb) isosceles geometries. Spectroscopic consequences of this situation are discussed, vibronic spectra are predicted and compared to laser-induced fluorescence spectra obtained in helium droplet isolation spectroscopy experiments of our group.
我们比较了由钾和铷形成的同核和异核碱三原子的 3(4)A(1)和 4(4)B(2)态。应用二级多参考瑞利-薛定谔微扰理论获得相应的绝热势能面。在同核三聚体的情况下，这两对态对应于 E⊗e Jahn-Teller 扭曲的 2(4)E'态的两个分支。对于异核三聚体，振动模式 Q(x)和 Q(y)不再简并，但这两个电子态在钝角 (KRb(2)) 或锐角 (K(2)Rb)等腰几何形状下仍然显示出锥形交叉。讨论了这种情况的光谱后果，预测了振子光谱，并将其与我们小组在氦液滴隔离光谱实验中获得的激光诱导荧光光谱进行了比较。
