NH (interstellar molecule)

Interstellar NH was discovered in 1991 by D. M. Meyer and K. C. Roth. NH is reported in the diffuse clouds toward Zeta Per and HD 27778 from high-resolution high S/N spectra of the NH A 3Pi-X 3Sigma (0,0) absorption band near 3358 A. These observations represent the first detection of this molecule anywhere in the interstellar medium.

Chemistry

Within diffuse clouds H- + N --> NH + e- is a major formation mechanism. Near chemical equilibrium important NH formation mechanisms are recombinations of NH2+ and NH3+ ions with electrons. Depending on the radiation field in the diffuse cloud, NH2 can also Contribute.

NH is destroyed in diffuse clouds by photodissociation and photionization. In dense clouds NH is destroyed by reactions with atomic Oxygen and Nitrogen. O+ and N+ form OH and NH in diffuse clouds. NH is involved in creating N2, OH, H, CN+, CH, N, NH2+,NH+ for the interstellar medium.