Microwave spectra for five isotopomers of iron dinitrosyl dicarbonyl were measured in the 4-16-GHz range using a Flygare-Balle type spectrometer. Numerous b-dipole transitions were observed for Fe(NO)2(CO)2, Fe15NONO(CO)2, Fe(15NO)2(CO)2, Fe(15NO)213COCO, and 54Fe(15NO)2(CO)2. Measured rotational constants were analyzed to obtain an accurate gas-phase structure. Some of the structural parameters obtained are ZN-Fe-N = 121(2)°, 〈C-Fe-C = 101(2)°, r(Fe-N) = 1.69(2) Å, r(Fe-C) = 1.85(2) Å, 〈Fe-N-O = 176(2)°, and 〈Fe-C-O = 177(2)°. NMR and IR data are also given. Nitrogen quadrupole coupling tensors were obtained from hyperfine structure on transitions for Fe(14NO)2(CO)2 and Fe(14NO)(15NO)(CO)2. The z principal axis for the quadrupole tensor is rotated 62° away from the Fe-N bond direction and principal axis components are eQqzz = -1.5 MHz, eQqxx = 1.0 MHz and eQqyy = 0.53 MHz.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry