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Updated: Aug 23, 2026

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Vibrational frequencies and structural determination of Al(8)S(12)
1US Army Edgewood Chemical and Biological Center, Aberdeen Proving Ground, MD 21010-5424, USA. jim.jensen@us.army.mil
Abstract:
The normal mode frequencies and corresponding vibrational assignments of Al(8)S(12) in T(h) symmetry are examined theoretically using the Gaussian98 set of quantum chemistry codes. All normal modes were successfully assigned to one of four types of motion (Al-S stretch, Al-S-Al bend, S-Al-S bend, and Al-S-Al wag) predicted by a group theoretical analysis. Normal mode frequencies are predicted and calculated infrared intensities and Raman activities are presented. The thermodynamics of the reaction 2Al(4)S(6)-->Al(8)S(12) are examined.
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