Fourier transform spectra of the 3300 cm^-1 bands of HCN

The 3300-cm^-1 bands of various isotopes of HCN have been measured with a resolution of about 0.01 cm^-1 using the Fourier transform spectrometer constructed by J. Brault and co-workers at the National Solar Observatory. The frequencies of 910 HCN lines obtained from absorption spectra of three different isotopic species are reported with an accuracy of approximately 0.0001 cm^-1. Six bands of HCN, four bands of H¹³CN, and two bands of HC¹⁵N were analyzed to obtain band origins, rotational constants, and l-doubling constants. The first (11¹0 ← 01¹0) and second (12⁰0 ← 02⁰0 and 12²0 ← 02²0) hot bands of H¹³CN are measured at high resolution for the first time. The fine structures of the Q branches of (110 ← 010), (12²0 ← 02²0), and (13³0 ← 03³0) "hot bands" of HCN have been completely resolved and measured. The accuracies of the calculated band origins are better than 0.0001 cm^-1 for most bands, and the upper state rotational constants (B′) have accuracies which range from 1 × 10^-7 to 5 × 10^-6 cm^-1 (0.003 to 0.015 MHz).