Laser vaporization generation of Al12C, Al13C, Al12C2, and Al13C2 for rare gas matrix electron spin resonance studies: Experimental-theoretical comparisons
Knight, L. B.; Cobranchi, S. T.; Herlong, J. O.; Arrington, C. A. Laser vaporization generation of Al12C, Al13C, Al12C2, and Al13C2 for rare gas matrix electron spin resonance studies: Experimental-theoretical comparisons. J. Chem. Phys. 1990, 92, 5856-5856.
The metalcarbide radicals AlC and AlC2 have been generated by the laser vaporization of aluminumcarbide and trapped in neon and argon matrices at 4 K for electron spin resonance(ESR) characterization. These results provide the first experimental evidence showing that AlC has a 4Î£ ground electronic state and that AlC2 is X-€‰ 2 A 1. A b i n i t i o theoretical calculations were conducted for the geometries and various nuclear hyperfine parameters in both radicals which yielded A values in reasonable agreement with the observed. In AlC, the three unpaired electrons reside primarily on carbon with the following neon matrix magnetic parameters (MHz): g -ˆ¥=2.000(1); g -Š¥=2.0010(5); -€–A -Š¥(Al)-€–=33.2(5); -€–A -ˆ¥(Al)-€–=3(3); A -Š¥(13C)=52.1(5); A -ˆ¥(13C)=52(2); and D(zero field splitting)=374(1). For AlC2, the spin density resides predominantly in an aluminum 3p z /3s hybrid directed away from C2. The neon magnetic parameters (MHz) are: g -ˆ¥=2.0005(5); g -Š¥=1.9965(3); A -Š¥(Al)=941.5(5); A -ˆ¥(Al)=1067(1); -€–A -ˆ¥(13C)-€–=59(1); and -€–A -Š¥(13C)-€–=52(1).
Journal of Chemical Physics