Premium
High‐temperature infrared and Raman spectra of aluminium chloride dimer and monomer in the vapour phase
Author(s) -
Tomita T.,
Sjøgren C. E.,
Klaeboe P.,
Papatheodorou G. N.,
Rytter E.
Publication year - 1983
Publication title -
journal of raman spectroscopy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.748
H-Index - 110
eISSN - 1097-4555
pISSN - 0377-0486
DOI - 10.1002/jrs.1250140611
Subject(s) - raman spectroscopy , chemistry , dimer , analytical chemistry (journal) , infrared spectroscopy , infrared , spectral line , chloride , matrix isolation , monomer , polymer , organic chemistry , physics , astronomy , optics
The infrared spectra of aluminium chloride vapour (Al 2 Cl 6 and AlCl 3 ) including Al 2 35 Cl 6 and Al 2 37 Cl 6 at 473–843 K were measured in the region 700–50 cm −1 with an evacuable Fourier transform spectrometer by transmission and emission techniques. Evacuable cells of nickel were employed having windows of type IIa diamond and sealed with gold O‐rings. Raman spectra of Al 2 Cl 6 vapour at ca 500 K and of AlCl 3 at 1075 K with pressures from 0.3 to 10 atm were recorded, polarization measurements were carried out and additional spectra of the 35 Cl and 37 Cl compounds were obtained. The dimer spectra were interpreted in terms of D 2h symmetry. All the nine Raman‐active and seven of the infrared‐active dimer fundamentals were assigned. The IR active mode ν 10 ( B 1u ), expected below 40 cm −1 , and the inactive mode ν 5 ( A u ) were left unassigned. The monomer spectra were interpreted in terms of D 3h symmetry and all four fundamentals were assigned. A dimer force field, involving 12 independent force constants, was derived. The calculated frequencies were fitted with a least‐squares programme to 30 observed fundamentals of Al 2 35 Cl 6 and Al 2 37 Cl 6 and 14 additional isotopic shifts transferred from previous matrix isolation spectra. A complete force field for the monomer was derived, using the four observed fundamentals and seven isotopic shifts transferred from previously reported matrix isolation spectra.