Fourier transform infrared emission spectra of MgH and MgD

Abstract

High resolution Fourier transform infrared emission spectra of MgH and MgD have been recorded. The molecules were generated in an emission source that combines an electrical discharge with a high temperature furnace. Several vibration-rotation bands were observed for all six isotopomers in the X (2)Sigma(+) ground electronic state: v=1-->0 to 4-->3 for (24)MgH, v=1-->0 to 3-->2 for (25)MgH and (26)MgH, v=1-->0 to 5-->4 for (24)MgD, v=1-->0 to 4-->3 for (25)MgD and (26)MgD. The new data were combined with the previous ground state data, obtained from diode laser vibration-rotation measurements and pure rotation spectra, and spectroscopic constants were determined for the v=0 to 4 levels of (24)MgH and the v=0 to 5 levels of (24)MgD. In addition, Dunham constants and Born-Oppenheimer breakdown correction parameters were obtained in a combined fit of the six isotopomers. The equilibrium vibrational constants (omega(e)) for (24)MgH and (24)MgD were found to be 1492.776(7) cm(-1) and 1077.298(5) cm(-1), respectively, while the equilibrium rotational constants (B(e)) are 5.825 523(8) cm(-1) and 3.034 344(4) cm(-1). The associated equilibrium bond distances (r(e)) were determined to be 1.729 721(1) A for (24)MgH and 1.729 157(1) A for (24)MgD.

Fourier transform infrared emission spectra of MnH and MnD

“…The vibrational bands v = 1 fi 0 to v = 3 fi 2 for MnH and v = 1 fi 0 to v = 4 fi 3 for MnD were observed. Analyses of the new spectra have provided improved ground state molecular constants for MnH and MnD.The same emission source that has proved to be very effective in providing spectra of other metal hydrides in our laboratory was used for MnH and MnD [12,13]. The infrared spectra of MnH/D were recorded between 800 and 1700 cm À1 at a resolution of 0.0085 cm À1 .…”

“…The same emission source that has proved to be very effective in providing spectra of other metal hydrides in our laboratory was used for MnH and MnD [12,13]. The infrared spectra of MnH/D were recorded between 800 and 1700 cm À1 at a resolution of 0.0085 cm À1 .…”

OPTICAL ZEEMAN SPECTROSCOPY OF THE (0, 0)A2Π-X2Σ+BAND SYSTEM OF MAGNESIUM HYDRIDE

“…The rotational, B (=5.7365078 cm −1 ), spin-rotational, γ (=2.63897 × 10 −2 cm −1 ), Fermi contact, b F (=1.0269 × 10 −3 cm −1 ), and dipolar, c (=1.598 × 10 −4 cm −1 ), parameters were held fixed at values determined from the analysis of the millimeter wave spectrum (Ziurys et al 1993). The centrifugal distortion correction to rotation, D (=3.543234 × 10 −4 cm −1 ), was held fixed at the value determined from the analysis of the tunable far-infrared spectrum (Zink et al 1990), whereas the centrifugal distortion correction to spin-rotation, γ D (=−5.77 × 10 −6 cm −1 ), was held fixed to the value obtained from the analysis of the Fourier transform infrared emission spectrum (Shayesteh et al 2004). A 4 × 4 matrix representation, constructed using a Hund's case (a βJ ), nonparity basis set, Ψ = |nΛ; SΣ; (JI)FΩM F >, was diagonalized to produce the eigenvalues and eigenvectors.…”

“…There have been no previous molecular beam optical spectroscopic studies of MgH. An extensive study of the field-free visible emission spectrum of MgH recorded at near Dopplerlimited resolution using Fourier transform spectroscopy has been reported by the Bernath group (Shayesteh & Bernath 2011;Shayesteh et al 2007Shayesteh et al , 2004Bernath et al 1985). A comprehensive review of the numerous spectroscopic studies performed on this molecule over the past century can be found in those publications.…”

Division Xii/Commission 14/Working Group on Molecular Data

“…Laboratory vibration-rotation spectra for a considerable number of metal hydrides are known with recent measurements of, for example, BeH (Shayesteh et al 2003a), MgH (Shayesteh et al 2004a), and CaH (Shayesteh et al 2004b); even the metal dihydrides BeH 2 (Shayesteh et al 2003b) and MgH 2 (Shayesteh et al 2003c) have been detected in the laboratory. Although metal hydrides such as MgH and CaH are detected in stellar atmospheres by their electronic transitions, there have been no infrared astronomical observations.…”