@article {2482, title = {Fourier transform microwave spectrum of and Born-Oppenheimer breakdown effects in tungsten monoxide, WO}, journal = {Canadian Journal of Physics}, volume = {87}, number = {5}, year = {2009}, note = {ISI Document Delivery No.: 494RVTimes Cited: 0Cited Reference Count: 33Krumrey, Christine Cooke, Stephen A. Russell, Douglas K. Gerry, Michael C. L.}, month = {May}, pages = {567-573}, type = {Article}, abstract = {Rotational transitions of eight isotopomers of tungsten monoxide, WO, in its X0(+) ground electronic state, have been measured in the frequency range 22-26 GHz, using a cavity Fourier transform microwave spectrometer. The samples were prepared by laser ablation of W metal in the presence of O-2 and stabilized in pulsed supersonic jets of Ne or Ar. Only the J = 1-0 transition was accessible within the frequency range of the spectrometer. It was measured for the ground (nu = 0) and two excited (nu = 1, 2) vibrational states. Hyperfine structure due to W-183 nuclear spin-rotation coupling was found for (WO)-W-183. The overall spectral fit used a Dunham-type expression including Born-Oppenheimer breakdown parameters. Only the nu = 0 and 1 states could be fit to the measurement accuracy because of a small perturbation of the nu = 2 state. It was necessary to account for the finite nuclear size of the W nucleus in the fit. The resulting parameter V-01(W) agreed well with a value calculated using density functional theory. Equilibrium internuclear distances re have been evaluated.}, keywords = {COUPLING CASE C, DIATOMIC-MOLECULES, DUNHAM COEFFICIENTS, ENERGY, FIELD SHIFT, INFRARED-SPECTRA, ISOTOPE DEPENDENCE, PB-CHALCOGENIDES, ROTATIONAL SPECTRUM, TL-HALIDES}, isbn = {0008-4204}, url = {://000269834000014}, author = {Krumrey, C. and Cooke, S. A. and Russell, D. K. and Gerry, M. C. L.} } @article {826, title = {Microwave spectra, nuclear field shift effects, geometries and hyperfine constants of bismuth mononitride, BiN, and bismuth monophosphide, BiP}, journal = {Journal of Molecular Structure}, volume = {695}, year = {2004}, note = {ISI Document Delivery No.: 827SVTimes Cited: 11Cited Reference Count: 66Sp. Iss. SI}, month = {Jun}, pages = {13-22}, type = {Article}, abstract = {The diatomic molecules BiN and BiP have been prepared using a laser ablation technique and studied by Fourier transform microwave spectroscopy in the frequency range 7-22 GHz. For BiN, only the J = 1-0 transition fell within this range. Transitions for the ground and first excited vibrational states have been observed for both (BiN)-N-14 and (BiN)-N-15. For BiP, which has only one isotopomer, the transitions J{\textquoteright}-J" = 1-0. 2-1 and 3-2 have been observed, but only for the ground vibrational state. Hyperfine structure has been observed for both nuclei in both molecules the Bi-209 nuclear quadrupole coupling constants show that the electronic structures are similar for the two molecules. Improved bond lengths have been obtained for both molecules. Density functional methods have been used to estimate the electron density at the bismuth nucleus in each molecule and hence allow an estimate of the uncertainty due to field shift effects in the experimentally derived bond lengths. (C) 2003 Elsevier B.V. All rights reserved.}, keywords = {BII, BiN, BiP, BORN-OPPENHEIMER APPROXIMATION, Born-Oppenheimer breakdown, DIATOMIC-MOLECULES, DUNHAM COEFFICIENTS, FOURIER-TRANSFORM SPECTROSCOPY, GROUND-STATE, HIGH-RESOLUTION, HYPERFINE, IODIDE, ISOTOPE DEPENDENCE, microwave spectra, MOMENTS, nuclear field shift effects, QUADRUPOLE, ROTATIONAL SPECTRUM, STRUCTURE}, isbn = {0022-2860}, url = {://000221922000003}, author = {Cooke, S. A. and Michaud, J. M. and Gerry, M. C. L.} } @article {410, title = {The electronic spectrum of NiCN in the visible region}, journal = {Journal of Molecular Spectroscopy}, volume = {215}, number = {1}, year = {2002}, note = {ISI Document Delivery No.: 601LETimes Cited: 18Cited Reference Count: 74}, month = {Sep}, pages = {106-127}, type = {Article}, abstract = {The electronic spectrum of NiCN in the 500-630 nm region has been observed by laser-induced fluorescence, following the reaction of laser-ablated nickel atoms with cyanogen under free jet expansion conditions. Seven electronic states hake been identified. Three of these, (X) over tilde (1) (2)Delta(5/2), (X) over tilde (2) (2)Delta(3/2), and (W) over tilde (2)(1)Pi(3/2), are derived from the electron configuration Ni+ (3d(8) 4s) CN, and the other four, (A) over tilde (2) Delta(5/2), (B) over tilde (2)Pi(3/2), (C) over tilde (2)Phi(7/2) and (D) over tilde (2)Phi(5/2), are derived from the configuration Ni+ (3d(8) 4s) CN. Rotational analysis of bands of (NiCN)-N-14 and (NiCN)-N-15 at high resolution has given the bond lengths in the (X) over tilde (2)(1)Delta(5/2) ground state as r(0) (Ni-C) = 1.8292 +/- 0.0028 Angstrom; r(0) (C-N) = 1.1591 +/- 0.0029 Angstrom. The orbital angular momentum splits the bending fundamental of the (X) over tilde (2)(1)Delta(5/2) state into two vibronic components, which lie at 243.640 cm(-1) ((2)Pi(3/2)) and 244.964 cm(-1) ((2)Phi(7/2)). Exceptionally strong Fermi resonance occurs in the ground state between the Ni-C stretching vibration, nu(3), and the overtone of the bending vibration. Sixty vibrational levels of the ground state with /l/ = 0 and l have been assigned, They could tie fitted by least squares to a simple matrix representation of the Fermi resonance that ignores the orbital angular momentum the interaction matrix element, as a fraction of the bending frequency, turns out to be larger than that in the "prototype" molecule, CO2. The two low-lying excited electronic states, (X) over tilde (2)Delta(3/2) at 830 cm(-1) and (W) over tilde (2)(1)Pi(3/2) at 2238 cm(-1), have very similar properties to the ground state. The energies of the excited states in the visible region bear a remarkable resemblance to those found in NiH (S, A. Kadavathu et al., 1991, J. Mol. Spectrosc. 147, 448-470). Again, the effects of Fermi resonance in them are large but those of vibronic coupling are surprisingly small. The most significant vibronic coupling occurs between the (A) over tilde (2)Delta(5/2) and (B) over tilde (2)Pi(3/2) states, which are separated by 79 cm(-1), an interval which is less than half the frequency of the bending vibration that couples them large numbers of vibronically induced bands appear in the excitation and dispersed emission spectra, but the splitting between (tie vibronic components of the bending fundamental of the (A) over tilde (2)Delta(5/2) state is only 6.988 cm(-1). Rotational perturbations are widespread in the (A) over tilde (2)Delta(5/2) state, particularly in the levels of the nu(3) (Ni-C stretching) progression, Vibrational assignments have been made on the basis of the Ni-58-Ni-60 isotope shifts at high resolution and the Franck-Condon patterns in dispersed emission spectra, Various weak unassigned bands, both in the excitation and the dispersed emission spectra, give evidence for the existence of at least three more excited electronic states which it has not been possible to characterize in detail. (C) 2002 Elsevier Science (USA)}, keywords = {ANION PHOTOELECTRON-SPECTROSCOPY, EXCITED-STATES, FOURIER-TRANSFORM SPECTROSCOPY, LASER-INDUCED FLUORESCENCE, LITHIUM ISOCYANIDE, LOW-LYING STATES, MG-BEARING, MICROWAVE, MOLECULE, POTENTIAL-ENERGY SURFACE, ROTATIONAL SPECTRUM, SPECTROSCOPY}, isbn = {0022-2852}, url = {://000178446800011}, author = {Kingston, C. T. and Merer, A. J. and Varberg, T. D.} } @article {5173, title = {Microwave spectrum, structure, and hyperfine constants of Kr-AgCl: Formation of a weak Kr-Ag covalent bond}, journal = {Journal of Molecular Spectroscopy}, volume = {206}, number = {1}, year = {2001}, note = {ISI Document Delivery No.: 428BNTimes Cited: 29Cited Reference Count: 38}, month = {Mar}, pages = {33-40}, type = {Article}, abstract = {The pure rotational spectrum of the complex Kr-AgCl has been measured between 8-15 GHz using a cavity pulsed-jet Fourier transform microwave spectrometer. The complex was found to be linear and relatively rigid, with a Kr-Ag bond length of similar to2.641 Angstrom. The Kr-Ag stretching frequency was estimated to be 117 cm(-1). Ab initio calculations performed at the MP2 level of theory gave the geometry, vibration frequencies, Kr-Ag bond dissociation energy, and orbital populations. The Kr-Ag bond dissociation energy was estimated to be -28 kJ mol(-1). The Kr-Ag force constant and dissociation energy are greater than those of Ar-Ag in Ar-AgCl. The chlorine nuclear quadrupole coupling constants show slight changes on complex formation. Ab initio orbital population analysis shows a small shift in sigma -electron density from Kr to Ag on complex formation. The combined experimental and ab initio results are consistent with the presence of a weak Kr-Ag covalent bond. (C) 2001 Academic Press}, keywords = {ATOMS, COMPLEXES, CORRELATED MOLECULAR CALCULATIONS, DER-WAALS, FOURIER-TRANSFORM SPECTROSCOPY, GAUSSIAN-BASIS SETS, LASER-ABLATION, RAMAN, ROTATIONAL SPECTRUM, STABILITY, TRANSITION-METAL COMPLEXES}, isbn = {0022-2852}, url = {://000168441400004}, author = {Reynard, L. M. and Evans, C. J. and Gerry, M. C. L.} } @article {4794, title = {The microwave spectra and structures of Ar-AgX (X=F,Cl,Br)}, journal = {Journal of Chemical Physics}, volume = {112}, number = {3}, year = {2000}, note = {ISI Document Delivery No.: 271MWTimes Cited: 68Cited Reference Count: 46}, month = {Jan}, pages = {1321-1329}, type = {Article}, abstract = {The rotational spectra of the complexes Ar-AgF, Ar-AgCl, and Ar-AgBr have been observed in the frequency range 6-20 GHz using a pulsed jet cavity Fourier transform microwave spectrometer. All the complexes are linear and rather rigid in the ground vibrational state, with the Ar-Ag stretching frequency estimated as similar to 140 cm(-1). Isotopic data have been used to calculate an r(0) structure for Ar-AgF, while for Ar-AgCl and Ar-AgBr partial substitution structures have also been obtained. To reduce zero-point vibrational effects a double substitution method (r(d)) was employed to calculate the structures of Ar-AgCl and Ar-AgBr. The Ar-Ag bond distance has been found to be rather short and to range from 2.56 Angstrom in Ar-AgF to 2.64 Angstrom in Ar-AgBr. Ab initio MP2 and density functional theory calculations for Ar-AgF and Ar-AgCl model the geometries and stretching frequency well, and predict an Ar-Ag bond energy in Ar-AgF of similar to 23 kJ mol(-1). These results indicate that the Ar-AgX complexes are more strongly bound than typical van der Waals complexes. Analysis of the halogen nuclear quadrupole coupling constants was unable to confirm whether extensive electron rearrangement occurs upon formation of the complexes. (C) 2000 American Institute of Physics. [S0021-9606(00)02202-9].}, keywords = {ARGON VANDERWAALS COMPLEX, DER-WAALS COMPLEXES, ELECTRONIC SPECTROSCOPY, INTERATOMIC POTENTIALS, LASER-ABLATION, METAL ATOMS, PHOTODISSOCIATION SPECTROSCOPY, PHOTOIONIZATION, RARE-GAS COMPLEXES, ROTATIONAL SPECTRUM, SPECTROSCOPY}, isbn = {0021-9606}, url = {://000084598900029}, author = {Evans, C. J. and Gerry, M. C. L.} } @article {4792, title = {Noble gas-metal chemical bonding? The microwave spectra, structures, and hyperfine constants of Ar-CuX (X = F, Cl, Br)}, journal = {Journal of Chemical Physics}, volume = {112}, number = {21}, year = {2000}, note = {ISI Document Delivery No.: 315YCTimes Cited: 72Cited Reference Count: 40}, month = {Jun}, pages = {9363-9374}, type = {Article}, abstract = {The rotational spectra of the complexes Ar-CuF, Ar-CuCl, and Ar-CuBr have been observed in the frequency range 5-22 GHz using a pulsed-jet cavity Fourier transform microwave spectrometer. All the complexes are linear and rather rigid in the ground vibrational state, with the Ar-Cu stretching frequency estimated as similar to 200 cm(-1). Isotopic data have been used to calculate an r(0) structure for Ar-CuF, while for Ar-CuCl and Ar-CuBr partial substitution structures have also been obtained. To reduce zero-point vibrational effects a double substitution method (r(d)) has also been employed to calculate the structures of Ar-CuCl and Ar-CuBr. The Ar-Cu distance has been found to be rather short and to range from 2.22 Angstrom in Ar-CuF to 2.30 Angstrom in Ar-CuBr. Ab initio calculations at the MP2 level of theory model the geometries and stretching frequencies well and predict an Ar-Cu bond energy in Ar-CuF of similar to 47.3 kJ mol(-1). Large changes in the Cu nuclear quadrupole coupling constant on complex formation show that extensive charge rearrangement occurs upon formation of the complexes. This, in conjunction with the sizable dissociation energy, suggests that the Ar-Cu bonds in these complexes are weakly covalent. The rotational spectrum of CuF has also been reinvestigated to improve the hyperfine constants. (C) 2000 American Institute of Physics. [S0021-9606(00)00521-3].}, keywords = {2ND, ARGON VANDERWAALS COMPLEX, ATOMS, COMPLEXES, CORRELATED MOLECULAR CALCULATIONS, DER-WAALS, FOURIER-TRANSFORM SPECTROSCOPY, GAUSSIAN-BASIS SETS, ROTATIONAL SPECTRUM, STATES}, isbn = {0021-9606}, url = {://000087139700021}, author = {Evans, C. J. and Gerry, M. C. L.} } @article {4796, title = {Noble gas-metal chemical bonding: the microwave spectra, structures and hyperfine constants of Ar-AuF and Ar-AuBr}, journal = {Physical Chemistry Chemical Physics}, volume = {2}, number = {18}, year = {2000}, note = {ISI Document Delivery No.: 353RKTimes Cited: 47Cited Reference Count: 33}, pages = {3943-3948}, type = {Article}, abstract = {The rotational spectra of the complexes Ar-AuF and Ar-AuBr have been observed in the frequency range 7-22 GHz using a pulsed-jet cavity Fourier transform microwave spectrometer. Both complexes are linear and rather rigid in the ground vibrational state, with the Ar-Au stretching frequency estimated as similar to 200 cm(-1). Isotopic data have been used to calculate an r(0) structure for Ar-AuBr while for Ar-AuF only an estimation of the r(0) geometry could be made. Ab initio calculations at the MP2 level of theory model the geometries and stretching frequencies well and predict an Ar-Au bond energy in Ar-AuF of similar to 60 kJ mol(-1). The Au nuclear quadrupole coupling constant changes significantly on complex formation, indicating extensive charge arrangement. This in conjunction with the large dissociation energy and ab initio results show that the Ar-Au bonds in these complexes are weakly covalent in nature.}, keywords = {ARGON, COMPLEXES, CORRELATED MOLECULAR CALCULATIONS, FOURIER-TRANSFORM SPECTROSCOPY, GAUSSIAN-BASIS SETS, NQR, RAMAN, ROTATIONAL SPECTRUM, STATES}, isbn = {1463-9076}, url = {://000089289100001}, author = {Evans, C. J. and Rubinoff, D. S. and Gerry, M. C. L.} } @article {4147, title = {Nuclear hyperfine interactions in the microwave spectrum of aluminium isocyanide}, journal = {Chemical Physics Letters}, volume = {278}, number = {1-3}, year = {1997}, note = {ISI Document Delivery No.: YF643Times Cited: 23Cited Reference Count: 34}, month = {Oct}, pages = {9-15}, type = {Article}, abstract = {The pure rotational spectrum of AINC has been measured between 11.9 and 24.0 GHz using a pulsed jet Fourier transform microwave spectrometer. The molecule was produced using a laser ablation source, in which the ablated Al metal reacted with cyanogen present in the Ar backing gas of the jet. Hyperfine structure due to both the Al-27 and N-14 nuclei has been observed. Nuclear quadrupole coupling constants and nuclear spin-rotation constants have been determined for both nuclei along with an Al-N nuclear spin-spin coupling constant. The electronic structure of AINC has been investigated by estimating the degree of sp-hybridisation of the Al and N bonding orbitals. Comparisons have been made to similar linear metal isocyanide and aluminium halide species. (C) 1997 Elsevier Science B.V.}, keywords = {ABINITIO, ALCL, interactions, IRC+10216, MG-BEARING MOLECULE, MILLIMETER, PREDICTION, ROTATIONAL SPECTRUM, SPECTROMETER, spectroscopic constants, SPIN}, isbn = {0009-2614}, url = {://A1997YF64300002}, author = {Walker, K. A. and Gerry, M. C. L.} } @article {3774, title = {Microwave Fourier transform spectroscopy of perchloryl fluoride: (FClO3)-F-19-Cl-35/37-O-16 and (FClO2O)-F-19-Cl-35/37-O-16-O-18}, journal = {Journal of Molecular Spectroscopy}, volume = {175}, number = {1}, year = {1996}, note = {ISI Document Delivery No.: TX208Times Cited: 18Cited Reference Count: 81}, month = {Jan}, pages = {120-132}, type = {Article}, abstract = {O-18-enriched, monolabeled perchloryl fluoride, (FClO2O)-F-19-Cl-35/37-O-16-O-18, has been synthesized. Its rotational spectrum has been studied in the 4-22 GHz region. In addition, the spectra of the symmetric isotopomers (FClO3)-F-19-Cl-35/37-O-16 have been reinvestigated. Rotational and centrifugal distortion constants, as well as chlorine nuclear quadrupole and chlorine and fluorine spin-rotation and spin-spin coupling constants, have been determined for the ground vibrational state. The ground state rotational data have been used to evaluate geometrical parameters. The harmonic force field has been refined. The results are compared with data of related molecules. (C) 1996 Academic Press. Inc.}, keywords = {BANDS, BOND LENGTHS, COUPLING-CONSTANTS, FCLO3, FORCE-CONSTANTS, N-F, NU-2, ROTATIONAL SPECTRUM, SPECTROMETER, STATES}, isbn = {0022-2852}, url = {://A1996TX20800017}, author = {Muller, H. S. P. and Gerry, M. C. L.} } @article {3571, title = {PULSED-BEAM MICROWAVE FOURIER-TRANSFORM MEASUREMENTS ON ISOTOPICALLY SUBSTITUTED VAN-DER-WAALS DIMER NE-OCS}, journal = {Journal of Molecular Spectroscopy}, volume = {169}, number = {2}, year = {1995}, note = {ISI Document Delivery No.: QD984Times Cited: 12Cited Reference Count: 23}, month = {Feb}, pages = {542-554}, type = {Article}, abstract = {Pure rotational spectra of seven isotopomers of Ne-OCS (Ne-OCS, Ne-22-OCS, Ne-21-OCS, Ne-(OCS)-O-18, Ne-(OCS)-C-13, Ne-(OCS)-S-34, and Ne-(OCS)-S-33) have been investigated using a pulsed jet cavity microwave Fourier transform spectrometer. Rotational and centrifugal distortion constants have been determined for all species, as well as the nuclear quadrupole coupling constants of S-33 and Ne-21 in Ne-(OCS)-S-33 and Ne-21-OCS, respectively. Harmonic force field analyses have been performed which account for the Variations in the distortion constants between the isotopomers. Effective and ground state average structures have been obtained and are discussed in light of the nuclear quadrupole coupling constants and of dipole moment measurements. The determined coupling constants have provided a means of comparing the effects of perturbation of the electronic structures of both constituents upon complexation. An electrostatic model has been applied to calculate the Ne-21 coupling constants and a possible source of their disagreement with experiment is discussed. (C) 1995 Academic Press, Inc.}, keywords = {AR, COMPLEXES, DIPOLE-MOMENTS, FORCE-FIELD, INFRARED-ABSORPTION, KR, KR-83, QUADRUPOLE, ROTATIONAL SPECTRUM, SPECTROSCOPY}, isbn = {0022-2852}, url = {://A1995QD98400022}, author = {Xu, Y. J. and Gerry, M. C. L.} } @article {7267, title = {THE MICROWAVE-SPECTRUM OF THE VANDERWAALS COMPLEX AR-N2}, journal = {Chemical Physics Letters}, volume = {196}, number = {3-4}, year = {1992}, note = {ISI Document Delivery No.: JH787Times Cited: 47Cited Reference Count: 34}, month = {Aug}, pages = {274-279}, type = {Article}, abstract = {The microwave spectrum of the van der Waals complex Ar-N2 has been investigated. N-15 quadrupole coupling constants, rotational and centrifugal distortion constants, structural parameters and an estimate of the dipole moment have been obtained. A value for the N-14 quadrupole coupling constant for free nitrogen has been derived.}, keywords = {ENERGY, HCN DIMER, J-DEPENDENCE, MOLECULE, N2-AR, NITROGEN, RADIOFREQUENCY, ROTATIONAL SPECTRUM, SPECTROSCOPY}, isbn = {0009-2614}, url = {://A1992JH78700009}, author = {Jager, W. and Gerry, M. C. L.} }