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摘要: 利用路径积分蒙特卡罗方法，基于Lax的半经典理论谱，研究了在T=5 K条件下，压力对固氢掺锂体系锂原子吸收谱的影响。结果表明，随着压力的增加，锂原子吸收谱半宽逐渐增加，而吸收谱的质心谱移随压力的增加，先向高能方向移动，达到最高点以后，又向低能方向移动。对具有低对称性结构的俘获点，压力导致三体吸收谱劈裂为单峰加双峰吸收谱，而且单峰和双峰间的距离随压力升高而增加。Abstract: We employ quantum path-integral Monte Carlo method to investigate the pressure-induced absorption spectra of Li in solid H2 at T=5 K and pressure ranging from 0 to 2.4 GPa, based on Lax's semiclassical spectral line theory. The pressure-induced effects on Li atomic absorption spectra associate with an increase in half-width and a centroid spectral shift, which experiences a blue shift below a turning pressure (pt) and a red shift above pt under study. For lower symmetrical trapping site structures, application of pressure also results in a change in absorption line shape from a low symmetrical triplet feature to a doublet plus singlet pattern, in which the doublet to singlet splitting increases remarkably with the increasing of pressure.
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Key words:
- path-integral Monte Carlo /
- lithium doped in solid H2 /
- Li absorption spectrum /
- pressure
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