低温下氘分子红外吸收特性研究

Infrared absorption of deuterium molecules at low temperature

采用基于第一性原理的从头计算单双取代耦合簇方法并结合cc-PVTZ基组,计算了处于基态的(D2)3分子两种不同构型(D2d和D2h)的各种能量模式及其对应的红外谱图.利用自主研制的低温平面冷冻靶系统和低温红外光谱测量系统获得了低温下液氘的红外吸收谱.结果表明,实验测得的液氘红外吸收最强位置与理论计算得到的基态(D2)3分子的红外强度最大位置基本一致,且均为低模式Q1(0)+S0(0).

The vibration/rotation modes and the corresponding infrared spectra of deuterium molecules with the D2d/D2h structures are calculated using the coupled cluster singles and doubles method with the cc-PVTZ basis sets within the framework of the density function theory. The infrared （IR） absorption spectrum of liquid deuterium is experimentally measured in a home-made cryogenic target system by a home-made low-temperature infrared spectroscope. The exper-imental results show that the strongest IR absorption peak of liquid deuterium is related to the Q1（0）＋S0（0） mode, which is in good agreement with the theoretical calculation.