HYPERFINE RESOLVED PURE ROTATIONAL SPECTROSCOPY OF ScN, YN, AND BaNH (X1_+): INSIGHT INTO METAL-NITROGEN BONDING

Fourier transform microwave spectroscopy coupled with a discharge-assisted laser ablation source (DALAS) has been used to record the J,=,1,$rightarrow$,0 pure rotational transitions of Sc$^{14}$N, Sc$^{15}$N, Y$^{14}$N, Y$^{15}$N, and Ba$^{14}$NH (X$^{1}Sigma^{+}$). Each species was synthesized by the reaction of the ablated metal with either NH$_{3}$ or $^{15}$NH$_{3}$ in the presence of a DC discharge. For each species hyperfine structure was resolved. In the case of ScN and YN hyperfine parameters (quadrupole and nuclear spin-rotation) for the metal and nitrogen were determined and for BaNH the nitrogen quadrupole coupling constant was measured. These hyperfine constants are interpreted to gain insight into the metal-nitrogen bonding in each species. In addition, DFT calculations were performed to assist with the assignment of each spectrum and the characterization of the metal-nitrogen bond