Infra-Red Absorption Spectrum of Diamond

Abstract

THE wording used by Krishnan and Ramanathan was “the centre of this fall (i.e. between the absorption maxima at 1285 and 1376 cm.¹) coincides with the Raman frequency at 1332 cm.¹”. Not unnaturally I took this to mean the minimum of absorption between these two peaks. Apparently what Krishnan and Ramanathan meant was the centre of the side of the band with peak at 1285 cm.¹. But this is an equally untenable position. All the arguments in my earlier letter still hold if one replaces “minimum of absorption" by "centre of the long-wave side of the absorption maximum”. Even their much milder statement in the above letter that “the absorption associated with the 1332 cm.¹ frequency is an integral part of the 8µ band” is open to question, as it depends on (a) the resolving power of the spectrometer used, and (b) the temperature at which the measurements are made.