Crystal absorption spectra for potassium octachlorodimolybdate(II) dihydrate

Journal Article · Mon Aug 01 04:00:00 EDT 1977 · Inorg. Chem.; (United States)

DOI:https://doi.org/10.1021/ic50174a057· OSTI ID:7078221

Fanwick, P E; Martin, D S; Cotton, F A; Webb, T R

Partial polarized crystal spectra are reported for K/sub 4/Mo/sub 2/Cl/sub 8/ x 2H/sub 2/O for both b and c polarization at 300 and 3.7/sup 0/K. The intense band in the visible region, ca. 19,000 cm/sup -1/, has been shown to possess molecular zto..pi.. polarization. This band was therefore assigned /sup 1/Au/sub 2u/ reverse arrow /sup 1/A/sub 1g/ (delta* reverse arrow delta). It is sufficiently intense that only the absorption due to a minority fraction could be recorded. At 3.7/sup 0/K, vibrational structure to the band can be resolved, but there are irregularities in the observed progression. A dipole-allowed but low-intensity transition was observed at 28,800 cm/sup -1/ with higher intensity in z--..pi.. polarization. It has been assigned as the A/sub 2/' reverse arrow A/sub 1/' component of a /sup 3/E/sub u/ reverse arrow /sup 1/A/sub 1g/ transition. This is a transition to the triplet state associated with the /sup 1/E/sub u/ reverse arrow /sup 1/A/sub 1g/ transition seen at 31,400 cm/sup -1/ in pellet and mull spectra, which was shown to be polarized x, y-sigma. Weak absorptions at 22,000--24,000 cm/sup -1/ appeared to be vibronic bands.

• Research Organization: Ames Lab., IA
• OSTI ID: 7078221
• Journal Information: Inorg. Chem.; (United States), Journal Name: Inorg. Chem.; (United States) Vol. 16:8; ISSN INOCA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ABSORPTION SPECTRA
ALKALI METAL COMPOUNDS
BAND THEORY
CRYSTALS
ENERGY-LEVEL TRANSITIONS
MOLYBDATES
MOLYBDENUM COMPOUNDS
MONOCRYSTALS
OXYGEN COMPOUNDS
POTASSIUM COMPOUNDS
SPECTRA
TRANSITION ELEMENT COMPOUNDS