Abstract Reflection-absorption IR (RAIR) spectra of sulfur hexafluoride (SF6) crystalline thin films in 10–100 K temperature range and absorption FTIR spectra of thin layer (90 μm) of liquid SF6 near the melting point (Tm = 222 K) are recorded. Special attention is paid to combinational bands region. The three types of band behavior upon phase transitions are identified and illustrated by 3ν6, ν1+ ν3, ν2+ ν3, ν1+ν4 and ν5+ν4 bands. The contours of the latter bands uncharacteristically change upon phase transitions. The different behavior of those bands is explained by the various contributions of different band forming mechanisms, evaluated by the mathematical apparatus of spectral moments.

中文翻译：

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SF6 薄膜在组合模式区域的反射吸收 FTIR 研究

摘要 六氟化硫 (SF6) 晶体薄膜在 10-100 K 温度范围内的反射吸收红外 (RAIR) 光谱和液态​​ SF6 薄层 (90 μm) 在熔点 (Tm = 222 K) 附近的吸收 FTIR 光谱是记录。特别注意组合带区域。通过 3ν6、ν1+ ν3、ν2+ ν3、ν1+ν4 和 ν5+ν4 能带识别和说明相变时的三种能带行为。后一种带的轮廓在相变时会发生异常变化。这些带的不同行为是由不同带形成机制的不同贡献来解释的，由光谱矩的数学装置评估。