First observation and electronic structure of the diatomic platinum nitride molecule

Journal Article · Sun May 01 04:00:00 EDT 1994 · Journal of Chemical Physics; (United States)

DOI:https://doi.org/10.1063/1.467078· OSTI ID:5003105

Friedman-Hill, E J; Field, R W ^[1]

---

1. George R. Harrison Spectroscopy Laboratory and the Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

The optical spectrum of the PtN radical has been observed directly for the first time. The strongest band system [(0,0) bandhead at 18 591 cm[sup [minus]1]] displays an unusual perpendicular [Delta][Omega]=0'' perturbation which gives rise to strong intensity cancellation effects. Although a [sup 4][Sigma][sup [minus]] ground state was expected for PtN, we have assigned the ground state as [sup 2][Pi][sub [ital r]]; a [sup 4][Sigma][sup [minus]] assignment is [ital not] consistent with our observations. We have used arguments based on both molecular orbital theory and atomic-ion-in-molecule theory to explain the observed ground state symmetry in light of the observed hyperfine structure. Four electronic bands involving a total of six Hund's case (c) [vert bar][ital v],[Omega][r angle] substrates have been rotationally analyzed, and many more bands have been observed at lower resolution. The ground state was found to have [Omega]=0.5 and its principal constants are [ital B][sub [ital e]]=0.455 708(5) cm[sup [minus]1], [alpha][sub [ital e]]=0.003 448 1(1) cm[sup [minus]1], spin--rotation constant [gamma][sub 0]=0.061 26(7) cm[sup [minus]1], [omega][sub [ital e]]=947.0(5) cm[sup [minus]1], and [omega][sub [ital e]x][sub [ital e]]=5.0(5) cm[sup [minus]1]. Two other [Omega] states were observed at low energies---an [Omega]=1.5 state at [ital T][sub [ital e]]=2 985.665(2) cm[sup [minus]1], with [ital B][sub 0]=0.445 233(8) cm[sup [minus]1], [ital q]=1.522(5)[times]10[sup [minus]6] cm[sup [minus]1], [omega][sub [ital e]]=901(1) cm[sup [minus]1], and [omega][sub [ital e]x][sub [ital e]]=8(1) cm[sup [minus]1], and another [Omega]=0.5 state with [ital T][sub [ital e]] undetermined and other constants remarkably similar to those of the ground state ([ital B])[sub 0]=0.453 07(6) cm[sup [minus]1], [gamma][sub 0]=0.062 02(4) cm[sup [minus]1], [omega][sub [ital e]]=947(1) cm[sup [minus]1], and [omega][sub [ital e]x][sub [ital e]]=5(1) cm[sup [minus]1].

• OSTI ID: 5003105
• Journal Information: Journal of Chemical Physics; (United States), Journal Name: Journal of Chemical Physics; (United States) Vol. 100:9; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

664200* -- Spectra of Atoms & Molecules & their Interactions with Photons-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ELECTRONIC STRUCTURE
ENERGY LEVELS
EXCITED STATES
GROUND STATES
HYPERFINE STRUCTURE
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
PLATINUM COMPOUNDS
RADICALS
RESOLUTION
ROTATIONAL STATES
TRANSITION ELEMENT COMPOUNDS