Gas-phase chemistry of nitrogen trifluoride NF3: structure and stability of its Mþ–NF3 (M ¼ H, Li, Na, K) complexes

The stationary points characterizing the potential energy profiles of the complex processes of the Mþ(M ¼ H, Li, Na, K) and NF3 were investigated by QCISD and B3LYP in conjunction with the 6-311 þ G(2d,2p) basis set. The optimized geometries and NBO analysis indicate that the complexes of Mþ(M ¼ Li, Na, K) and NF3 exist as ion-dipole molecules. But for Hþ complexes, there are two stable isomers NF3Hþ and NF2þ–HF. The interaction distances of isomers follow the sequence Hþ , Liþ , Naþ , Kþ. The calculated affinity energies of the most stable isomers of Hþ, Liþ, Naþ, and Kþ complexes exceed 20.1 kJ/mol, and these values suggest that the Mþ–NF3 (M ¼ H, Li, Na, K) complexes could be observed as stable species in gas phase, which supports Fujii’s proposal that Liþ ion attachment mass spectrometry can serve as a conceivable technique to quantify the emissions of the NF3. q 2003 Elsevier B.V. All rights reserved