MOLECULAR CONSTANTS FOR $CO_{2}$ AND ITS ISOTOPIC SPECIES FROM HETERODYNED LASER DATA

Abstract

Molecular constants of $^{12}$C$^{16}$O${2}$, $^{13}$C$^{16}$O${2}$ $^{12}$C$^{18}$O${2}$ and $^{13}$C$^{18}$O${2}$ for the Fermi diad ($10^{0}0, 02^{0}0$) were obtained using the absolute frequencies measured from laser heterodyne $techniques.^{1}$ The constants were evaluated by a numerical iterative procedure in which the rotational dependent part of the Fermi coupling element, $\delta$J(J + I), was included. The theoretical relations for isotopic substitution for this molecule are well satisfied.