Layered crystal structure, conformational and vibrational properties of 2,2,2-trichloroethoxysulfonamide: An experimental and theoretical study

详细信息    查看全文

• 作者：Diego M. Gil ; Oscar E. Piro ; Gustavo A. Echeverr¨ªa ; Mar¨ªa E. Tuttolomondo ; A¨ªda Ben Altabef
• 关键词：Crystal X-ray diffraction structure ; Ab initio MO calculations ; Natural bond orbital analysis ; Infrared and Raman spectroscopy
• 刊名：Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy
• 出版年：2013
• 出版时间：December, 2013
• 年：2013
• 卷：116
• 期：Complete
• 页码：122-131
• 全文大小：1137 K

文摘

The molecular structure of 2,2,2-trichloroethoxysulfonamide, CCl₃CH₂OSO₂NH₂, has been determined in the solid state by X-ray diffraction data and in the gas phase by ab initio (MP2) and DFT calculations. The substance crystallizes in the monoclinic P2₁/c space group with a = 9.969(3) ?, b = 22.914(6) ?, c = 7.349(2) ?, ¦Â = 91.06(3)¡ã, and Z = 8 molecules per unit cell. There are two independent, but closely related molecular conformers in the crystal asymmetric unit. They only differ in the angular orientation of the sulfonamide (SO₂NH₂) group. The conformers are arranged in the lattice as center-symmetric NH?O(sulf)-bonded dimers. Neighboring dimers are linked through further NH?O(sulf) bonds giving rise to a crystal layered structure. The solid state infrared and Raman spectra have been recorded and the observed bands assigned to the molecular vibration modes. Also, the thermal behavior of the substance was investigated by TG-DT analysis. The stability of the molecule arising from hyper-conjugative interactions and charge delocalization has been analyzed using natural bond (NBO) analysis.