Microwave spectrum of the HI—HF complex

Bumgarner, Roger E.; Cogley, C. D.; Kukolich, Stephen G.

doi:10.1016/0009-2614(85)87263-8

Cited by 8 publications

(3 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The first pulsed-beam Fourier transform (PBFT) microwave spectrometer (Flygare−Balle) and subsequent spectrometers − (to the best of our knowledge) employed superheterodyne microwave detection systems. This detection scheme offered substantial improvement in signal-to-noise ratio ( S / N ) over simple video detectors, as used on early Stark-cell spectrometers, and was probably the best choice available 15−26 years ago.…”

Section: Methodsmentioning

confidence: 99%

Microwave Spectra and Gas-Phase Structural Parameters of Bis(η⁵-cyclopentadienyl)tungsten Dihydride

et al. 2007

View full text Add to dashboard Cite

Microwave spectra for 11 isotopomers of bis(η 5 -cyclopentadienyl)tungsten dihydride ((C 5 H 5 ) 2 WH 2 ) were recorded in the 5-14 GHz region using a Flygare-Balle-type pulsed beam spectrometer. Spectra arising from four tungsten isotopomers of both the (C 5 H 5 ) 2 WH 2 and (C 5 H 5 ) 2 WHD species and three W isotopomers for the (C 5 H 5 ) 2 WD 2 complex have been measured. The ∼250 b-type transition frequencies assigned for these near-prolate asymmetric top molecules were accurately described (σ fit ) 2-4 kHz) using the rotational parameters A, B, and C and one centrifugal distortion constant, ∆ J . The small value obtained for ∆ J indicates a fairly rigid structure. From a least-squares fit using the resulting 33 rotational constants to obtain the molecular structure, we were able to determine the W-H bond length, r(W-H) ) 1.703(2) Å, the H-W-H bond angle, ∠(H-W-H) ) 78.0(12)°, the W-Cp centroid distance, r(W-Cp) ) 1.940(8) Å, the angle made by the Cp centroids with tungsten, ∠(Cp-W-Cp) ) 155(2)°, and the average C-C bond length, r(C-C) ) 1.429(8) Å. The hydrogen atom separation is r(H-H) ) 2.14(2) Å, indicating that this is clearly a "classical dihydride" rather than an "η 2 -dihydrogen" complex. The WH 2 moiety parameters determined from Kraitchman's equations (r(W-H) ) 1.682(2) Å, ∠(H-W-H) ) 78.6(2), r(H-H) ) 2.130(2) Å) agree well with the least-squares results. Furthermore, the r e parameters obtained from DFT calculations agree well with the experimental r 0 structural parameters. To our knowledge, this work marks the first microwave study of a bent-metallocene complex. The present measurements were made with a pulsed-beam Fourier transform spectrometer employing a homodynetype detection system, and this configuration is described. This homodyne system greatly simplifies the microwave circuit, with no apparent loss in sensitivity.

show abstract

Section: Methodsmentioning

confidence: 99%

Microwave Spectra and Gas-Phase Structural Parameters of Bis(η⁵-cyclopentadienyl)tungsten Dihydride

et al. 2007

View full text Add to dashboard Cite

show abstract

“…This spectrometer was constructed in our laboratory, 39 following the general design given by Balle and Flygare, 38 and modified for these experiments as discussed below. The sample of MnRe͑CO͒ 10 was placed into a glass sample cell, which is directly connected to the pulse valve.…”

Section: Methodsmentioning

confidence: 99%

The rotational spectrum and theoretical study of a dinuclear complex, MnRe(CO)10

Tanjaroon

Keck

Kukolich

et al. 2004

The Journal of Chemical Physics

View full text Add to dashboard Cite

The first rotational spectrum of a dinuclear complex, MnRe(CO)(10), has been obtained using a high-resolution pulsed beam microwave spectrometer. Sixty-four hyperfine components of the J=11-->J(')=12 and J=12-->J(')=13 rotational transitions were measured for two rhenium isotopomers. The B values obtained from the experiment are B=200.36871(18) MHz for the (187)Re isotopomer and B=200.5561(10) MHz for the (185)Re isotopomer. The measured rotational constants are in reasonably good agreement with the B values calculated from the x-ray diffraction structural data, and from theoretical calculations. The gas-phase Mn-Re bond distance is approximately 2.99 A, and the calculated value is only slightly longer. The experimental quadrupole coupling constant for the manganese atom is eQq(aa) ((55)Mn)=-16.52(5) MHz, and the corresponding quadrupole coupling constants for the two rhenium isotopomers are eQq(aa) ((187)Re)=370.4(4) MHz and eQq(aa) ((185)Re)=390.9(6) MHz. The quadrupole coupling constants were also determined from a variety of theoretical calculations, with very large Gaussian orbital bases. The best estimates, at a nonrelativistic level, are eQq(aa) ((55)Mn)=0.68 MHz and eQq(aa) ((187)Re)=327.6 MHz with a 874 GTO basis set, but the results are very basis set dependent, especially the sign of the Mn quadrupole coupling. Very slight bending of angles MnC(eq)O(eq) and ReC(eq)O(eq) angles is found in the calculations.

show abstract

“…Spectra were measured in the 4-13 GHz frequency range using a Fourier transform, pulsed beam microwave spectrometer system [6]. Rotational transitions due to the two most abundant titanium isotopomers, 47 Ti (I = 5/2) and 48 Ti (I = 0), were observed in the present experiment.…”

Section: Introductionmentioning

confidence: 99%

Rotational and hyperfine spectra for a sandwich titanium complex, C5H5TiC7H7

Keck

Tanjaroon

Kukolich

2005

Journal of Molecular Spectroscopy

View full text Add to dashboard Cite

Microwave spectrum of the HI—HF complex

Cited by 8 publications

References 8 publications

Microwave Spectra and Gas-Phase Structural Parameters of Bis(η⁵-cyclopentadienyl)tungsten Dihydride

Microwave Spectra and Gas-Phase Structural Parameters of Bis(η⁵-cyclopentadienyl)tungsten Dihydride

The rotational spectrum and theoretical study of a dinuclear complex, MnRe(CO)10

Rotational and hyperfine spectra for a sandwich titanium complex, C5H5TiC7H7

Contact Info

Product

Resources

About

Microwave spectrum of the HI—HF complex

Cited by 8 publications

References 8 publications

Microwave Spectra and Gas-Phase Structural Parameters of Bis(η5-cyclopentadienyl)tungsten Dihydride

Microwave Spectra and Gas-Phase Structural Parameters of Bis(η5-cyclopentadienyl)tungsten Dihydride

The rotational spectrum and theoretical study of a dinuclear complex, MnRe(CO)10

Rotational and hyperfine spectra for a sandwich titanium complex, C5H5TiC7H7

Contact Info

Product

Resources

About

Microwave Spectra and Gas-Phase Structural Parameters of Bis(η⁵-cyclopentadienyl)tungsten Dihydride

Microwave Spectra and Gas-Phase Structural Parameters of Bis(η⁵-cyclopentadienyl)tungsten Dihydride