LOW TEMPERATURE ABSORPTION SPECTRA OF CRO=4 INK2S04 AND VO=4 IN NA3PO4.12H20

The polarized absorption spectrum of the chromate ion has been measured at liquid hydrogen and helium temperatures. With chromate dissolved in K2SO4 evidence is found for two orbitally allowed 1A1→1T2 electronic absorption bands. The first band is split into three sublevels with the 0-0 lines located at 26,316 cm-1, 26,441 cm-1 and 26,610 cm-1. Built upon the 0-0 lines is seen a simple progression in quanta of 783 cm-1. The second transition is nearly featureless, and is found at 34,000 cm-1 to 44,000 cm-1. The two bands are assigned as primarily t1→2 e and as 3 t2→2 e respectively. VO4≡dissolved in Na3PO4 · 12H2O showed at liquid nitrogen temperature a broad featureless band found between 30,000 and 40,000 cm-1. © 1968 Springer-Verlag.