MgF_2:V^(2+)晶体能级和振动结构的DV-X_a研究

DV-X_a studies on the energy levels and vibrational structure of M_gF_2 : V^(2+) crystal

首次用DV-X_a方法计算了终端声子激光晶体MgF_2:V^(2+)的电子能级和振动结构,给出的晶场能级与实验值相当接近.使用晶格振动的“呼吸”模型,得到了基态~4B_(1g)和第一激发态~4B_(2g)的振动势能曲线.在简谐振动近似下,它们分别具有454cm^(-1)和460cm^(-1)的声子能量,与实验值399cm^(-1)符合很好.另外,还获得晶体振动的黄昆参数,激活能,和Franck—Condon交距等参数.计算了四种温度(0K,2K,77K和300K)下的振动线形,并与2K的实验吸收谱作了比较.

The energy levels and vibrational spectra of MgF2 : V2+ crystal are calculated by using discreate variational Xαmethod. The vibronic frequencies, Franck-Condon offset, Huang-Rhys parameter, and activation energy are obtained. The vibronic frequencies of ground state 4B1gand the first excited state 4B2gare 454 cm-1 and 460 cm-1, respectively, which are near the experimental value 399 cm-1. And the vibronic potentials in 0K, 2K, 77K and 300K are presented.