采用蒸发铍原子与非平衡态氢原子反应制备了透明的BeH2薄膜.扫描电子显微镜(SEM)观察到薄膜表面存在微孔洞,红外光谱显示在722 cm-1有一个强烈的吸收峰.采用密度泛函理论(DFT)对BeH2网状结构进行了计算,得到的3个基本振动模式的频率和强度与文献中BeH2粉末的实验数据基本一致,其中弯曲振动的计算频率为747 cm-1,与BeH2薄膜的红外吸收峰一致.推测BeH2薄膜的结构与BeH2粉末有所不同,因而导致某些振动峰被抑制.%Transparent BeH2 films have been prepared with vaporized beryllium atoms reacting with active hydrogen atoms.Scanning electron microscopy photographs show that the surfaces of BeH2 films have microvoids, and the infrared spectrum reveals an intense absorption band at 722 cm-1.BeH2 reticular structures based on tetrahedron structure have been calculated by density functional theory method.The frequency and intensity of three vibration modes obtained from the calculations are in reasonably good agreement with those observed in references for BeH2 powders.The calculated frequency of Be-H-Be bond bending vibrations is 747 cm-1 , which is consistent with the measured IR absorption band of BeH2 films in this paper.It can be speculated that the structures of BeH2 films are different from those of BeH2 powders, and thus some vibration modes are restrained.
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