nu(1) band of C-13 containing monodeuteroacetylene

nu(1)(Sigma(+)) <-- Ground state (Sigma(+)) band of C-13 containing monodeu teroacetylene ((C2HD)-C-13) has been experimentally observed for the first time. The band was detected during a systematic study of the high resolutio n Fourier transform infrared spectrum of (C2H2)-C-13 and C-12 C-13 H-2 mole cules in the 3 mu m region, recorded on a Bomem DA 3.002 FTIR spectrometer at an apodized resolution of 0.004 cm(-1). The estimated origin of the nu(1 ) band is at 3315.92 cm(-1). The line positions of the P and R branches are presented. The experimentally obtained rotational constants for the nu(1)( Sigma(+)) and GS(Sigma(+)) states are 0.94976 cm(-1) and 0.95424 cm(-1), re spectively.