@article {366,
	title = {Influence of the 6th and 10th spatial harmonics on the peak shape of a quadrupole mass filter with round rods},
	journal = {Rapid Communications in Mass Spectrometry},
	volume = {16},
	number = {15},
	year = {2002},
	note = {ISI Document Delivery No.: 578QXTimes Cited: 32Cited Reference Count: 32},
	pages = {1425-1431},
	type = {Article},
	abstract = {The influence of the ratio of the rod radius, r, to field radius, r(0), on the peak shape for a linear quadrupole mass filter constructed with round rods has been investigated. The expansion of the potential in multipoles, phi(N),Phi(x,y)= Sigma(N=0)(infinity)A(N)phi(N)/r(0)(N), has been considered, and the peak shape and resolution have been determined by numerical calculation of ion trajectories in quadrupoles with different ratios, r/r(0). Geometries that make the dodecapole term (A(6)) zero (r/(0) = 1.14511) do not give the best performance because the contribution of the 20-pole term, A(10), must be considered. The optimum ratio is r/r(0) approximate to 1.13. With this ratio the dodecapole term (A(6)) is ca. 1 x 10(-3), but its effects are partially compensated by the A(10) term which has similar magnitude, but opposite sign. Copyright (C) 2002 John Wiley Sons, Ltd.},
	keywords = {2ND, ION-TRAP, REGION, SIMULATION},
	isbn = {0951-4198},
	url = {<Go to ISI>://000177131400003},
	author = {Douglas, D. J. and Konenkov, N. V.}
}
@article {538,
	title = {Microwave spectra, geometries, and hyperfine constants of OCAgX (X = F, Cl, Br)},
	journal = {Inorganic Chemistry},
	volume = {41},
	number = {5},
	year = {2002},
	note = {ISI Document Delivery No.: 528TMTimes Cited: 17Cited Reference Count: 49},
	month = {Mar},
	pages = {1236-1244},
	type = {Article},
	abstract = {A pulsed jet cavity Fourier transform microwave spectrometer has been used to measure the rotational spectra of OCAgX (X = F, Cl, Br) in the frequency range 5-22 GHz, Metal atoms were generated via laser ablation and were allowed to react with CO and a halide precursor, prior to stabilization of the products within a supersonic jet of argon. These are the first experimental observations of OCAgF and OCAgBr, and the first high resolution spectroscopic study of OCAgCl. All three molecules are linear, Accurately determined rotational constants have been used to evaluate the various internuclear distances, which are found to be consistent with trends established for OCAuX and OCCuX species. The C-O distances are short, and the M-C distances are significantly longer than those in other molecules containing a metal-carbonyl bond, Precise values of centrifugal distortion constants and halogen nuclear quadrupole coupling constants have also been determined. The coupling constants are compared with the results of previous studies of OCCuX and OCAuX and are used to infer trends in the electron distributions of the molecules. Ab initio calculations have been performed and employed to predict the geometries, vibrational frequencies, and Mulliken valence orbital populations of the various species.},
	keywords = {2ND, ATOMS, COMPLEXES, CORRELATED MOLECULAR CALCULATIONS, CU(CO)CL, GAUSSIAN-BASIS SETS, LASER-ABLATION},
	isbn = {0020-1669},
	url = {<Go to ISI>://000174259300031},
	author = {Walker, N. R. and Gerry, M. C. L.}
}
@article {5217,
	title = {Microwave spectra, geometries, and hyperfine constants of OCCuX (X = F, Cl, Br)},
	journal = {Inorganic Chemistry},
	volume = {40},
	number = {24},
	year = {2001},
	note = {ISI Document Delivery No.: 492RMTimes Cited: 14Cited Reference Count: 45},
	month = {Nov},
	pages = {6158-6166},
	type = {Article},
	abstract = {A pulsed jet cavity Fourier transform microwave spectrometer has been used to measure the rotational spectra of OCCuX (X = F, Cl, Br) in the frequency range 5-21 GHz. Metal atoms were generated via laser ablation and were allowed to react with CO and a halide precursor, prior to stabilization of the products within a supersonic jet. These are the first experimental observations of OCCuF and OCCuBr and the first high-resolution spectroscopic study of gas-phase OCCuCl. All three molecules were found to be linear. Rotational constants, centrifugal distortion constants, nuclear quadrupole coupling constants, and nuclear spin-rotation coupling constants have been precisely determined. The rotational constants have been used to evaluate the various bond lengths, and the results are in good agreement with the trend established for OCAuX species. The C-O distance is found to be comparatively short and close to that of free CO. The M-C distance is longer than that predicted by ab initio calculations, and the Cu-X distances are very similar to those observed in the corresponding metal halides. Vibrational wavenumbers have been estimated from the distortion constants and are compared with the results of various ab initio studies. Changes in the Cu, Cl, and Br nuclear quadrupole coupling constants indicate that substantial charge rearrangement takes place on coordination with CO, consistent with the formation of strong Cu-C bonds. Mulliken orbital population analyses have been performed and provide evidence of pi -back-donation from Cu in all of the species studied. The evaluated nuclear spin-rotation coupling constants have been used to estimate the Cu-63 nuclear shielding constants, sigma, and their spans (Omega) in (OCCuF)-Cu-63, (OCCuCl)-Cu-63-Cl-35, and (OCCuBr)-Cu-63-Br-79.},
	keywords = {2ND, ATOMS, COMPLEXES, CORRELATED MOLECULAR CALCULATIONS, CU(CO)CL, GAUSSIAN-BASIS SETS, ROTATIONAL, SPECTRUM},
	isbn = {0020-1669},
	url = {<Go to ISI>://000172181400012},
	author = {Walker, N. R. 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 = {<Go to ISI>://000087139700021},
	author = {Evans, C. J. and Gerry, M. C. L.}
}
@article {4528,
	title = {Elemental analysis with quadrupole mass filters operated in higher stability regions},
	journal = {Journal of Analytical Atomic Spectrometry},
	volume = {14},
	number = {8},
	year = {1999},
	note = {ISI Document Delivery No.: 229LPTimes Cited: 23Cited Reference Count: 47},
	month = {Aug},
	pages = {1111-1119},
	type = {Article},
	abstract = {Operation of quadrupole mass filters in higher zones of stability is described with an emphasis on the potential for elemental mass spectrometry. The higher zones allow a resolution at half height of up to 9000 on atomic ions and make possible unit resolution on ions with kinetic energies up to several thousand electron volts. The theory of quadrupole operation is briefly reviewed. Operation of quadrupoles in the third stability region with Mathieu parameters (a,q)approximate to(3,3) and the second stability region with (a,q)approximate to(0.02, 7.55) is described in detail. Previously unpublished data showing the variation of resolution with ion energy are presented. The variation of transmission with resolution is compared with previous calculations and with new calculations presented here.},
	keywords = {2ND, ANALYZER, ATMOSPHERE, DIAGRAM, HELIUM, HIGH-RESOLUTION, ICP-MS, SEPARATION MODE, SPECTROMETER, ZONE},
	isbn = {0267-9477},
	url = {<Go to ISI>://000082196300002},
	author = {Du, Z. H. and Douglas, D. J. and Konenkov, N.}
}
@article {4526,
	title = {A novel tandem quadrupole mass analyzer},
	journal = {Journal of the American Society for Mass Spectrometry},
	volume = {10},
	number = {11},
	year = {1999},
	note = {ISI Document Delivery No.: 245ZBTimes Cited: 6Cited Reference Count: 18},
	month = {Nov},
	pages = {1053-1066},
	type = {Article},
	abstract = {A new "tandem mass analyzer" is described. Two quadrupole mass filters are operated in series. Each is operated at low resolution and a small mass offset is introduced between the two quadrupoles so that the pair operate together to give higher resolution. The resolution of the tandem analyzer can be changed by changing the mass offset. The transmission is highest when the quadrupoles are operated as close together as possible with the poles aligned, with no intervening ion lens, and with the radio frequency (rf) voltages phase locked. A phase shift between the rf voltages applied to the quadrupoles also improves the ion transmission. Far a given resolution the tandem analyzer has transmission comparable to that of a single quadrupole. Results obtained with operation of the quadrupoles in the first, second, and third stability regions are described. Operation in the third stability region is particularly advantageous because the tandem analyzer exhibits good abundance sensitivity on the low and high mass sides under conditions where a single quadrupole produces a long peak tail on at least one side. It is also shown that scattering losses in the tandem analyzer are about half of those of a conventional quadrupole. The results suggest that it may be possible to build a low cost tandem analyzer that has relatively poor mechanical precision and yet that produces satisfactory peak shape and resolution. (J Am Soc Mass Spectrom 1999, 10, 1053-1066) (C) 1999 American Society for Mass Spectrometry.},
	keywords = {2ND, FILTER, INTERMEDIATE STABILITY REGIONS, RESOLUTION},
	isbn = {1044-0305},
	url = {<Go to ISI>://000083137500001},
	author = {Du, Z. H. and Douglas, D. J.}
}
@article {2908,
	title = {THE EQUILIBRIUM PAIR DISTRIBUTION FUNCTION OF A GAS - ASPECTS ASSOCIATED WITH THE PRESENCE OF BOUND-STATES},
	journal = {Journal of Chemical Physics},
	volume = {99},
	number = {11},
	year = {1993},
	note = {ISI Document Delivery No.: MJ902Times Cited: 1Cited Reference Count: 36},
	month = {Dec},
	pages = {9111-9121},
	type = {Article},
	abstract = {At thermal equilibrium the momentum distribution of atoms in a gas is usually assumed to be Maxwellian, whether classically or quantally. However, if an atom is bound in a diatomic molecule, the atom{\textquoteright}s momentum distribution is non-Maxwellian. This paper explores the consequent singlet and pair particle distribution functions in a gas having both unbound atoms and bound pairs of atoms. Comment is made on the range of behavior associated with whether the chemical equilibrium constant for diatom formation is small or large. Calculations of distribution functions and their moments for atoms which are members of dimers are presented for some specific model potentials.},
	keywords = {2ND, DIMER, formation, INITIAL DENSITY DEPENDENCE, KINETIC-THEORY, PHASE-SPACE SUBDIVISION, POTENTIALS, TEMPERATURE, THERMAL-CONDUCTIVITY, TRANSPORT-PROPERTIES, VIRIAL-COEFFICIENT, VISCOSITY},
	isbn = {0021-9606},
	url = {<Go to ISI>://A1993MJ90200074},
	author = {Rainwater, J. C. and Snider, R. F.}
}
