Theoretical dissociation, ionization, and spin–orbit energetics of the diatomic platinum hydrides PtH, PtH+, and PtH

Spin–orbit configuration interaction (SO-CI) and coupled-cluster [CCSDT(Q)] theoretical methods are combined to evaluate zero-temperature thermochemical properties of PtH, PtH+, and PtH−. We obtain vibrational zero-point energies and spin–orbit stabilization energies, which lead to predictions for observable quantities: ionization energy IE(PtH) = (9.44 ± 0.07) eV; electron affinity EA(PtH) = (1.65 ± 0.04) eV; and dissociation energies D0(Pt–H) = (329.6 ± 3.9) kJ mol−1, D0(Pt+–H) = (279.3 ± 5.7) kJ mol−1, and D0(Pt−–H) = (285.0 ± 2.4) kJ mol−1 (uncertainty coverage factor = 2). Compared with available experiments, our value of D0(Pt+–H) is higher by (8 ± 8) kJ mol−1, EA(PtH) is higher by 0.15 eV, and D0(Pt–H) is lower than the upper bound by (2 ± 4) kJ mol−1.