The second group integral of cesium

Abstract

The literature data on the interaction of two cesium atoms, obtained by processing the results of spectroscopic experiments and quantum-mechanical calculations, are used to calculate the second group integral of cesium at temperatures from 700 to 3000 K. The contributions made by atoms in the ground 2 S and first excited 2 P electronic states are taken into account. The contribution by the excited state is negligible at 1000 K, approximately 2% at 2000 K, and as significant as 20% at 3000 K. The error of calculation results is estimated to range from 0.3% at the lowest temperatures to 10% at the highest temperatures.