Microwave Spectra and Structure of Ar-1,3-Difluorobenzene.

The microwave spectrum of the dimer Ar-1,3-difluorobenzene from 2 to 18 GHz is reported. The spectrum has been observed using a chirped-pulse Fourier transform microwave (CP-FTMW) spectrometer that has recently been expanded to include the 2-6 GHz region of the electromagnetic spectrum. Details of this upgraded spectrometer are reported.

Rotational Spectrum, Structure, and Interaction Energy of the Trifluoroethylene···Carbon Dioxide Complex.

Rotational spectra for four isotopologues of the 1:1 weakly bound complex between trifluoroethylene (HFC═CF) and carbon dioxide (CO) were recorded using 480 MHz bandwidth chirped-pulse and resonant cavity Fourier transform microwave spectroscopy between 5.0 and 18.5 GHz.

Effect of aromatic ring fluorination on CHπ interactions: microwave spectrum and structure of the 1,2-difluorobenzeneacetylene dimer.

Rotational spectra for the normal isotopic species and for six additional isotopologues of the 1,2-difluorobenzeneacetylene (C6H4F2HCCH) weakly bound dimer have been assigned in the 6-18 GHz region using chirped-pulse Fourier-transform microwave spectroscopy. This is the third complex in a series of fluorinated benzeneacetylene dimers. In 1,2-difluorobenzeneHCCH, the Hπ distance (2.

Characterization of two isomers of the vinyl fluoride···carbon dioxide dimer by rotational spectroscopy.

Rotational spectra of two different structural forms of the 1:1 weak complex between vinyl fluoride (C2H3F) and carbon dioxide were measured using 480 MHz bandwidth chirped-pulse and resonant cavity Fourier-transform microwave spectroscopy in the 5-17 GHz region. Both structures have the CO2 molecule situated in the plane of the vinyl fluoride, such that the CO2 is interacting either with a CHF side or with a HC═CF edge of the vinyl fluoride subunit. Both observed structures are close to those predicted by ab initio geometry optimizations (corrected for basis set superposition error) at the MP2/6-311++G(2d,2p) level.

Benzene···acetylene: a structural investigation of the prototypical CH···π interaction.

The structure of a prototype CH···π system, benzene···acetylene, has been determined in the gas phase using Fourier-transform microwave spectroscopy. The spectrum is consistent with an effective C(6v) structure with an H···π distance of 2.4921(1) Å.