Franck-Condon (FC) integrals of polyatomic molecules are computed on the basis of vibrational self-consistent-field (VSCF) or configuration-interaction (VCI) calculations capable of including vibrational anharmonicity to any desired extent (within certain molecular size limits). The anharmonic vibrational wave functions of the initial and final states are expanded unambiguously by harmonic osci...

We present high-resolution (R = 20000) spectroscopy of H+ 3 absorption toward the luminous Galactic center sources GCS 3-2 and GC IRS 3. With the efficient wavelength coverage afforded by Subaru IRCS, six absorption lines of H+ 3 have been detected in each source from 3.5 to 4.0μm, three of which are new. In particular the 3.543μm absorption line of the R(3,3) transition arising from the metast...

Context. Hydrogenation reactions of CO in interand circumstellar ices are regarded as an important starting point in the formation of more complex species. Previous laboratory measurements by two groups on the hydrogenation of CO ices resulted in controversial results on the formation rate of methanol (2002, ApJ, 577, 265 and 2002, ApJL, 571, L173). Aims. Our aim is to resolve this controversy ...

The astronomical gas-phase detection of simple species and small organic molecules in cold pre-stellar cores, with abundances as high as ~10-10 nH, contradicts the generally accepted idea that at 10 K, such species should be fully frozen out on grain surfaces. A physical or chemical mechanism that results in a net transfer from solid-state species into the gas-phase offers a possible explanatio...

We present high-resolution (R = 20000) spectroscopy of H+3 absorption toward the luminous Galactic center sources GCS 3-2 and GC IRS 3. With the efficient wavelength coverage afforded by Subaru IRCS, six absorption lines of H+3 have been detected in each source from 3.5 to 4.0 μm, three of which are new. In particular the 3.543 μm absorption line of the R(3, 3) transition arising from the metas...

Context. Hydrogenation reactions are expected to be among the most important surface reactions on interstellar ices. However, solid state astrochemical laboratory data on reactions of H-atoms with common interstellar ice constituents are largely lacking. Aims. The goal of our laboratory work is to determine whether and how carbon dioxide (CO2), formic acid (HCOOH) and acetaldehyde (CH3CHO) reac...

Aims. To establish the chemical origin of a set of complex organic molecules thought to be produced by grain surface chemistry in high mass young stellar objects (YSOs). Methods. A partial submillimeter line-survey was performed toward 7 high-mass YSOs aimed at detecting H2CO, CH3OH, CH2CO, CH3CHO, C2H5OH, HCOOH, HNCO and NH2CHO. In addition, lines of CH3CN, C2H5CN, CH3CCH, HCOOCH3, and CH3OCH3...