The ultra-violet band-system of germanium monoxide

Abstract

The GeO band-system, recently investigated by Shaw between λ2989 and λ2441 in the flame surrounding an arc charged with GeO2, has been measured over the larger range λ3319-λ2441 in an uncondensed discharge through a mixture of GeCl4 vapour and oxygen flowing continuously through the discharge tube. The number of bands measured is increased from 18 to 32, and the highest observed value of νdouble prime from 5 to 10. The band-heads of the extended system are approximately represented by ν=37762.4 + (651.3u' - 4.24u'2) - (985.7udouble prime - 4.30udouble prime2), where u = ν + ½. This system being attributed to 74GeO, a few other observed heads may be due to 72GeO and 70GeO. Rotational analysis being impossible, there is no further evidence for or against the transition 1Π r arr over l arr 1σ suggested by Shaw. The data are compared with those for band-systems of other monoxides and monosulphides of group-IVb elements, and the observed decreases of νe, ωe and xeωe with increasing atomic number or mass of either atom are shown graphically.