A synchrotron radiation study of high-lying excited states of matrix-isolated atomic magnesium

Abstract

Previous steady-state and time-resolved luminescence spectroscopy of 3p 1 P 1 atomic magnesium, isolated in thin film samples of the solid rare gases, is extended to include the higher energy 4p 1 P 1 excitation. Well-resolved site splittings are recorded in Mg/Ar samples for excitation to the 4p 1 P 1 level. A small red shift in the absorption energy to the 4p 1 P 1 level for Mg/Ar contrasts with a small blue shift on absorption to the 3p 1 P 1 level. Direct emission from the 4p 1 P 1 level is not observed in any of the rare gas matrices; instead, intense emission from the low energy 3p 1 P 1 level is. Measurements of the emission decay curves in Mg/Ar have revealed slow rates in the steps feeding the 3p 1 P 1 level following 4p 1 P 1 excitation. The reason for the differential shifting of the 4p 1 P 1 and 3p 1 P 1 levels as well as the lack of direct 4p 1 P 1 emission is thought to be related to the strong binding interaction between Mg in the 4p 1 P 1 state and the rare gases.

Density Functional Theory Study of Fe(CO)3(η2-C3H6), HFe(CO)3(η3-C3H5), and the Iron−Allyl Bond Energy

“…Thus, if there is only one stable isomer for a singlet ground state, an excited state of Fe(CO) 3 (η 2 -C 3 H 6 ) would have to account for the second isomer that is observed experimentally. Various isomers that can coexist on the ground state potential energy surface of a molecule have been observed, including less thermodynamically favored species. , However, there is little precedent for the long-term stability of an electronically excited state in a matrix environment since such states can potentially relax via both radiative and nonradiative processes. , Thus, we feel the most likely interpretation of this matrix experiment is that the two observed species are the two triplet isomers. On the basis of these data and the aforementioned data on rate constants for addition reactions we feel that the weight of evidence is clearly on the side of a triplet ground state for Fe(CO) 3 (η 2 -C 3 H 6 ).…”

The application of synchrotron radiation and in particular X-ray absorption spectroscopy to matrix isolated species

“…Whilst intense line sources (both laser and gas discharge) are available for laboratory based vac-UV experiments, SR vac-UV provide a tuneable source of radiation, which is especially useful for selective excitation experiments. Examples include the study of matrix isolated: Ag [287]; Cu [288]; Xe [289]; Cl [290]; Hg [291]; Cd [292]; Zn, Cd, Hg [293]; Mg atoms [294];…”

Effects of trapping site on the spectroscopy of 1P1 excited group 12 metal atoms in rare gas matrices

“…Matrix-isolation, specifically using rare gas solids as host materials, is an experimental technique that provides one of the most useful model systems to explore such phenomena. Despite the existence of numerous experimental studies that have been conducted in these model solids, [1][2][3][4][5][6][7] the site occupied by the guest metal atom still represents one of the major unknowns in matrix-isolation spectroscopy. As site occupancy is essential for understanding the complex dynamics of the trapped guest in its excited states, we have pursued the group 12 elements Zn, Cd and Hg since these metal atoms have been the subject of detailed experimental studies, most notably using excitation spectroscopy.…”