Assuming no interaction between vibrational and rotational energy levels in HF , the frequency (in $\mathrm{cm}^{-1}$, rounded off to the nearest integer) of the R branch line originating from $\mathrm{J}=4$ in its IR spectrum is ____ (Given: Rotational constant for $\mathrm{HF}=19.35 \mathrm{cm}^{-1} ; \overline{\mathrm{v}}_{0}=4138.52 \mathrm{cm}^{-1}$ )
Answer
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