The MCD spectrum of matrix-isolated osmium tetroxide

✍ Scribed by T.J. Barton; R. Grinter; A.J. Thomson

• Publisher: Elsevier Science
• Year: 1976
• Tongue: English
• Weight: 335 KB
• Volume: 40
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(76)85105-6

✦ Synopsis

The MCD spectrum of OS04 in argon and nitrogen matrices at CJ 20 K has been measured and is remarkably similar the first band of MrtOz in KI04 at 4.2 K. From this it is concluded that there are two e!ectronic origins in the region 30 000-39 000 cm-' and the spectrum of 0~04 is reassigned accordingly. to Despite many years of intensive investigation, the assignment of the electronic transitions in do tetraoxoanions is still in considerable doubt [ I-31. In recent years MCD spectroscopy [4-S] has played an important role in elucidating the nature of the transitions occurring in these compounds, and it has now been established with a reasonable degree of certainty that the lowest energy intense band is caused by the transition 'Al + IT2 (t$ + t: 2e1) [l]. However in the case of osmium tetroxide [9, lo] ~ notwithstanding MCD studies both in soliltion [S, 61 and in the gas phase [I 11, there is still some doubt concerning the assignment of the longest waveiength transition. A solution study of 0~0~ [6] has shown that the MCD signal associated with the lowest energy absorption band (2: 35 000 cm-l) contains a negative A term (A/D = -0.30) and h positive B term; the value of -0.3p for AID being very close to the theoretical val-