Electronic and vibrational spectroscopy and vibrationally mediated photodissociation of V+(OCO)

Citir M., ALTINAY G., METZ R.

JOURNAL OF PHYSICAL CHEMISTRY A, cilt.110, sa.15, ss.5051-5057, 2006 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 110 Sayı: 15
  • Basım Tarihi: 2006
  • Doi Numarası: 10.1021/jp060375s
  • Dergi Adı: JOURNAL OF PHYSICAL CHEMISTRY A
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.5051-5057
  • Abdullah Gül Üniversitesi Adresli: Hayır

Özet

Electronic spectra of gas-phase V+(OCO) are measured in the near-infrared from 6050 to 7420 cm(-1) and in the visible from 15500 to 16560 cm(-1), using photofragment spectroscopy. The near-IR band is complex, with a 107 cm(-1) progression in the metal-ligand stretch. The visible band shows clearly resolved vibrational progressions in the metal-ligand stretch and rock, and in the OCO bend, as observed by Brucat and coworkers. A vibrational hot band gives the metal-ligand stretch frequency in the ground electronic state v(3)" = 210 cm(-1). The OCO antisymmetric stretch frequency in the ground electronic state (v(1)") is measured by using vibrationally mediated photodissociation. An IR laser vibrationally excites ions to v(1)" = 1. Vibrationally excited ions selectively dissociate following absorption of a second, visible photon at the v(1)' = 1 <- v(1)" = 1 transition. Rotational structure in the resulting vibrational action spectrum confirms that VI(OCO) is linear and gives v(1)" = 2392.0 cm(-1). The OCO antisymmetric stretch frequency in the excited electronic state is v1' = 2368 cm(-1). Both show a blue shift from the value in free CO2, due to interaction with the metal. Larger blue shifts observed for complexes with fewer ligands agree with trends seen for larger V+(OCO)(n) clusters.

Electronic spectra of gas-phase V+(OCO) are measured in the near-infrared from 6050 to 7420 cm-1 and in the visible from 15 500 to 16 560 cm-1, using photofragment spectroscopy. The near-IR band is complex, with a 107 cm-1 progression in the metal−ligand stretch. The visible band shows clearly resolved vibrational progressions in the metal−ligand stretch and rock, and in the OCO bend, as observed by Brucat and co-workers. A vibrational hot band gives the metal−ligand stretch frequency in the ground electronic state ν3‘ ‘ = 210 cm-1. The OCO antisymmetric stretch frequency in the ground electronic state (ν1‘ ‘) is measured by using vibrationally mediated photodissociation. An IR laser vibrationally excites ions to ν1‘ ‘ = 1. Vibrationally excited ions selectively dissociate following absorption of a second, visible photon at the ν1‘ = 1 ← ν1‘ ‘ = 1 transition. Rotational structure in the resulting vibrational action spectrum confirms that V+(OCO) is linear and gives ν1‘ ‘ = 2392.0 cm-1. The OCO antisymmetric stretch frequency in the excited electronic state is ν1‘ = 2368 cm-1. Both show a blue shift from the value in free CO2, due to interaction with the metal. Larger blue shifts observed for complexes with fewer ligands agree with trends seen for larger V+(OCO)n clusters.