The A–X system of the CuCl molecule
The A–X band system of CuCl has been photographed in emission under high resolution in the 2nd order of a 10.6 m concave grating spectrograph. Rotational structure in four bands, viz. (1,0), (0,0), (0,1), and (1,2) has been analysed. The present analysis confirms that in the A–X system the electronic transition involved is 1Π–1Σ where 1Σ is the ground state of the molecule. The Λ-type doubling in the 1Π state is found to be appreciable. The molecular constants for the excited A state of 63Cu35Cl are (with standard deviations in parentheses): Be = 0.168432(7) cm−1; αe = 0.001067(7); De = 0.1134(11) × 10−6; q = 0.000871(9); qD = 0.85(18) × 10−8; ν10 = 19 500.271(8); ν00 = 18 999.104(7); ν01 = 18 579.735(10); and ν12 = 18 574.745(11).