dc.creator Forthomme, D. en_US dc.creator Tokaryk, D. W. en_US dc.creator Linton, C. en_US dc.creator Adam, A. G. en_US dc.date.accessioned 2011-07-12T17:32:47Z dc.date.available 2011-07-12T17:32:47Z dc.date.issued 2011 en_US dc.identifier 2011-FC-10 en_US dc.identifier.uri http://hdl.handle.net/1811/49493 dc.description Author Institution: Centre for Laser, Atomic, and Molecular Sciences and Physics Department, 8 Bailey Dr., University of New Brunswick, P.O. Box 4400, Fredericton, NB, Canada E3B 5A3; Centre for Laser, Atomic, and Molecular Sciences and Chemistry Department, 30 Dineen Dr., University of New Brunswick, P.O. Box 4400, Fredericton, NB, Canada E3B 5A3 en_US dc.description.abstract High resolution spectra have been analyzed for the $\tilde{A}^{2}$E$-\tilde{X}^{2}$A$_1$ transition of M-$^{12}$C$^{12}$CH, M-$^{12}$C$^{12}$CD and M-$^{13}$C$^{13}$CH, where M refers to Mg, Ca and Sr. All the molecules except CaCCH and SrCCH have been recorded and analyzed in our laboratory in a laser ablation molecular jet source. The rotational constants extracted from the fits allowed us to calculate accurate bond lengths in MgCCH, CaCCH and SrCCH. This study is of particular interest since it shows how the structure of the molecules evolves as we substitute the alkaline earth atom by another one from the same family. The results showed clear trends in how the molecules account for changes in the mass of the metal atom and how the bond lengths in the ligand CCH are significantly different from the bond lengths in HCCH. Surprisingly, the triple bond between the two carbon atoms happens to be the one that experiences the greatest change. To determine the three bond lengths in a linear four atom molecule, one requires spectral data from three isotopologues of that molecule. By combining information from previously published analyses with new high resolution isotopically substituted spectra, we have determined the bond lengths for MgCCH, CaCCH and SrCCH. In each case, the $\tilde{A}^{2}\Pi-\tilde{X}^{2}\Sigma^+$ spectra of the M-$^{12}$C$^{12}$CH, M-$^{12}$C$^{12}$CD and M-$^{13}$C$^{13}$CH isotopologues were considered, where M refers to Mg, Ca and Sr. This study is of particular interest since it shows how the structure of this family of molecules evolves as we change the alkaline earth atom attached to the CCH ligand. In MgCCH, the structure of the CCH ligand is nearly the same as it is in acetylene, HCCH. Surprisingly, the bonding in the ligand is quite different from that of acetylene for the two heavier acetylide molecules, with the triple bond between the two carbon atoms experiencing the greatest change. %The results show that the metal-carbon bond increases in length as the larger heavier %clear trends in how the molecules account for changes in the mass of the metal atom and how the bond lengths in the ligand CCH are significantly different from the bond lengths in HCCH. Surprisingly, the triple bond between the two carbon atoms happens to be the one that experiences the greatest change. en_US dc.language.iso en en_US dc.publisher Ohio State University en_US dc.title DETERMINATION OF THE BOND LENGTHS IN MgCCH, CaCCH and SrCCH en_US dc.type Article en_US
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