Direct-potential-fit analysis of new infrared and UV/visible AΣ+1-XΣ+1 emission spectra of AgH and AgD

Abstract

New high-resolution infrared and UV/visible spectra of (107)AgH, (109)AgH, (107)AgD, and (109)AgD have been recorded with a Fourier transform spectrometer. The new line positions are combined with published microwave and older electronic A (1)Sigma(+)-X (1)Sigma(+) data and used, first in a decoupled analysis of the X state alone, and then in a global multi-isotopologue analysis which yields comprehensive descriptions of both the X (1)Sigma(+) and A (1)Sigma(+) states of all four isotopologues of AgH. While the A state was long believed to be heavily perturbed, it is shown that its irregular spectrum merely reflects an unusual potential function shape. A direct fit of all data to appropriate radial Hamiltonians yields analytic potential-energy functions and Born-Oppenheimer breakdown radial functions for the ground X (1)Sigma(+) and A (1)Sigma(+) states.

Rotational spectra, potential function, Born–Oppenheimer breakdown and magnetic shielding of SiSe and SiTe

“…(9) to experimental transition frequencies yields a fairly compact set of empirical parameters, and the resulting potential energy and radial correction functions may also be used to predict other system properties. Details can be found in LeRoy's papers [23][24][25], which the reader is referred to for more information concerning the DPF method and for the explanation of the relevant quantities.…”

“…Recently, it has become increasingly common to perform spectroscopic data analysis of diatomic molecules employing fully quantum mechanic direct potential fit (DPF) methods [23,24]. In this approach the spectra are explained in terms of the properties of a potential energy function and associated mass-dependent BOB radial strength functions [20,25].…”

The rotational spectra, potential function, Born-Oppenheimer breakdown, and magnetic shielding of SnSe and SnTe

“…The full Dunham-type treatment described in the previous subsection implies that the spectra of all SnSe and SnTe isotopic species may be fully explained in terms of the properties of a potential energy function and associated massdependent BOB radial strength functions. 23,24,28 In practice, the observed vibrational-rotational level energies of a given isotopolog ͑␣͒ are accurately described as eigenvalues of the following radial Schrödinger equation: 24,29…”

Vibrational energies and full analytic potential energy functions of PbI and InI from pure microwave data

“…Using the synthetic data sets described above, DPF analyses were performed to determine an optimal model PEF for each species that will represent our synthetic experimental data as accurately as possible. In both cases the PEF model used was an "expanded Morse oscillator" (EMO) function, which has the form of a simple Morse potential in which the exponent coefficient can vary with distance [24][25][26][27][28]:…”