Microwave spectrum of P14N and P15N: Spectroscopic constants and molecular structure

In the present work the J+1←J, with J=1-3, 6, 7, 10-16, rotational transitions of P14N and the J+1←J, with J=1, 2, 7, 8, 10-14, rotational transitions of P15N have been observed in the millimeter- and submillimeter-wave region. These measurements allowed us to improve the ground state rotational parameters of P14N as well as provide those of P15N for the first time. The present measurements have been combined with rotational and vibrorotational transitions available in the literature to yield the Dunham coefficients. The equilibrium structure has also been determined to a high accuracy. The experimental investigation has been supported by highly accurate ab initio computations.