A STUDY OF THE (A)OVER-TILDE B-2(2)-(X)OVER-TILDE (2)A(1) BAND SYSTEMOF CANH2 EMPLOYING MOLECULAR-BEAM OPTICAL STARK SPECTROSCOPY

The 0(0)(0) (A) over tilde B-2(2) - (X) over tilde (2)A(1) visible ban d system of a supersonic molecular beam sample of calcium amide, CaNH2 , recorded in the presence of a variable static electric field has bee n studied using high resolution laser induced fluorescence spectroscop y. The determined spectroscopic parameters are (in cm(-1)), origin = 1 5 464.366 9(8); A'' = 13.057 4(9); B'' = 0.300 47(5); C'' = 0.292 88(5 ); epsilon''(bb) = 0.001 1(3); epsilon'(cc), = 0.001 1(3); A' = 11.448 7(2); B' = 0.307 1(1); C' = 0.299 2(1); epsilon'(aa) = 8.238(2); epsi lon'(bb) = 0.005 2(6); epsilon'(cc), = 0.055 7(6); Delta(k)(s) -0.060 8(5). The rotational parameters are interpreted to give an approximate r(0) structure. The large spin-rotation parameter for the (A) over ti lde(2)B(2) state is discussed in terms of a second order spin-orbit in teraction with other low-lying electronic states. Stark splitting of t he P-P(11)(1.5)+(P)Q(12)(0.5) branch feature was analyzed to produce a ground state permanent electric dipole moment, mu'', of 1.74(1) D. A comparison of mu'' with other monovalent calcium compounds is given. ( C) 1995 American Institute of Physics.