Knowledge Bank

“The absorption spectra of InCl was photographed using the Wisconsin 21-foot grating and 8 meters of absorbing vapor. The rotational lines of the B(0,0), A(0,0), A(0,1), and A(1,0) bands were identified and their wave numbers determined. An analysis was made of the effects of an incorrect numbering of the rotational lines on the combination differences $\Delta 1$F(J) and $\Delta 2$F(J), and on graphs of \frac{\Delta_{1}{F}({J})}{{J}+1}{ vs.}({J}+1)^{2}{ and }\frac{\Delta_{2}{F}({J})}{{J}+1/2}{ vs.}({J}+1/2)^{2} The analysis shows that a sensitive and complete test for determining the correct numbering requires (a) the equivalence of the combination relations, and (b) straight graph lines. Either (a) or (b) alone will not form a complete test. The numbering of the rotational lines in this study satisfied these tests. A rotational analysis gave the following values to the rotational constants for System A: These results agree, within the range of experimental error, with the value $ro=2.4012\times 10-8$ obtained from a microwave absorption experiment on InCl.”