The microwave spectrum and structure of phosphaethene, CH2=PH

1981 ◽  
Vol 34 (3) ◽  
pp. 465 ◽  
Author(s):  
RD Brown ◽  
PD Godfrey ◽  
D McNaughton
Keyword(s):  
Dipole Moment ◽  
Structural Parameters ◽  
Microwave Spectrum ◽  
Rotational Constants ◽  
Moments Of Inertia ◽  
Microwave Spectra ◽  
Isotopic Species

The microwave spectra of phosphaethene (methylenephosphine) and five of its isotopic species have been observed and assigned in the region 5-125 GHz. Rotational constants and moments of inertia have been determined for 12CH2PH, 13CH2PH, 12CD2PD, 12CD2PH, (Z)-12CHDPH and (E)-12CHDPH. The moments of inertia have been used to determine the following structural parameters: rP-H= 1.425�; rC-P= 1.671�; rC-H,= 1.082�; <HCP(Z) = 124.5�; <HCP(E) = 119.1�; <CPH = 95.5�. The dipole moment components have been determined as �a = 0.7233(7) D and �b = 0.4657(ll) D.

Microwave Spectrum, Structure, and Dipole Moment of Cyanogen Azide, NCN3

1972 ◽  
Vol 50 (13) ◽  
pp. 1453-1457 ◽  
Author(s):  
C. C. Costain ◽  
H. W. Kroto
Keyword(s):  
Dipole Moment ◽  
Stark Effect ◽  
Structural Parameters ◽  
Microwave Spectrum ◽  
Rotational Constants ◽  
Microwave Spectra ◽  
Isotopic Species ◽  
Planar Molecule ◽  
Spectrum Structure

The microwave spectra of cyanogen azide, NCN3, and two isotopic species have been investigated between 11 and 37 GHz. From the observed rotational constants, the following structural parameters have been obtained:[Formula: see text]The observed data are consistent with a planar molecule. The values of the rotational constants of the normal species are:[Formula: see text]The inertial defect for the normal species is 0.347 uÅ2.The dipole moment components have been determined from the Stark effect of several μa lines as μa = 2.93 ± 0.06 D and μb = 0.44 ± 0.015 D. The relatively low value of μb was responsible for the difficulty encountered in observing and assigning μb type transitions.

The microwave spectrum of propynethial, HC≡C-CHS

1982 ◽  
Vol 35 (9) ◽  
pp. 1747 ◽  
Author(s):  
RD Brown ◽  
PD Godfrey ◽  
R Champion ◽  
M Woodruff
Keyword(s):  
Dipole Moment ◽  
Pyrolysis Product ◽  
Microwave Spectrum ◽  
Rotational Constants ◽  
Flash Pyrolysis ◽  
Resonance Structures ◽  
Alternative Structures ◽  
Isotopic Species

We have demonstrated that the flash pyrolysis of dipropargyl sulfide yields propynethial, HC≡CCHS, among the products. The microwave spectrum of the major isotopic species of propynethial and of HCCCH34S have been analysed. The derived rotational constants for these species enable us to eliminate any alternative structures for the pyrolysis product. The measured dipole moment components [μa = 1.763(1) D; μb = 0.661(1); μtotal = 1.883(1)] are discussed in terms of simple resonance structures.

Mikrowellenspektrum, Hinderungspotential der internen Rotation und teilweise r0-Struktur des para-Chlortoluols

1967 ◽  
Vol 22 (5) ◽  
pp. 761-764 ◽  
Author(s):  
G. E. Herberich
Keyword(s):  
Internal Rotation ◽  
Structural Parameters ◽  
Rotational Constants ◽  
Methyl Group ◽  
Microwave Spectra ◽  
Isotopic Species ◽  
Nuclear Quadrupole

The rotational microwave spectra of the two chlorine isotopic species of para-chlorotoluene have been measured in the region from 8.4—11.3 GHz. Values for the rotational constants and for the nuclear quadrupole constants have been determined. The barrier to internal rotation of the methyl group is V6 = 13.93 ± 0.04 cal/mole. Two structural parameters have been estimated, namely 1.394 Å for the average ring C — C distance and 1.74 ± 0.01 A for the C — Cl distance.

Mikrowellenspektrum und rotationsspektroskopische Konstanten der Methylchlorsilane: CH3SiH2Cl, CH3SiD2Cl und CD3SiD2Cl / Microwave Spectrum and Rotational Spectroscopic Constants of Methyl-chloro-silane: CH3SiH2Cl, CH3SiD2Cl and CD3SiD2Cl

1975 ◽  
Vol 30 (11) ◽  
pp. 1441-1446
Author(s):  
W. Zeil ◽  
W. Braun ◽  
B. Haas ◽  
H. Knehr ◽  
F. Rückert ◽  
...  
Keyword(s):  
Microwave Spectrum ◽  
Coupling Constants ◽  
Spectroscopic Constants ◽  
Centrifugal Distortion ◽  
Rotational Constants ◽  
Microwave Spectra ◽  
Isotopic Species ◽  
Quadrupole Coupling ◽  
Nuclear Quadrupole ◽  
Centrifugal Distortion Constants

The microwave spectra of the following isotopic species of Methyl-chloro-silane: CH3SiH2Cl, CH3SiD2 and CD3SiD2Cl have been measured and the rotational spectroscopic constants (rotational constants, centrifugal distortion constants and nuclear quadrupole coupling constants) have been determined

The Microwave Spectrum, Dipole Moment, and Structure of Glycidol

1975 ◽  
Vol 53 (15) ◽  
pp. 2247-2251 ◽  
Author(s):  
W. V. F. Brooks ◽  
K. V. L. N. Sastry
Keyword(s):  
Hydrogen Bonding ◽  
Dipole Moment ◽  
Hydrogen Atom ◽  
Microwave Spectrum ◽  
Centrifugal Distortion ◽  
Total Dipole Moment ◽  
Hindered Rotation ◽  
Rotational Constants ◽  
Microwave Spectra ◽  
Centrifugal Distortion Constants

The microwave spectra of glycidol [Formula: see text] and its deuterated (—OD) form have been studied in the range 8–40 GHz. The rotational (in MHz) and centrifugal distortion constants (in kHz) of glycidol are: A = 10 347.87, B = 4102.36, C = 3781.95; ΔJ = 2.38, ΔJK = −311, ΔK = 5.2, δJ = 0.3159, δK = −9.76. The rotational constants and distortion constants of glycidol (OD) are A = 10 010.31, B = 4056.73, C = 3717.02; ΔJ = 2.53, ΔJK = 197, ΔK = 7.7,δJ = 0.3532,δK = −7.19. The dipole moment components of the normal molecule in Debye units are μa = 0.61, μb = 1.20, μc = 0.52, and the total dipole moment is 1.44 D.A structure is derived with the alcoholic hydrogen atom close (2.5 Å) to the ring oxygen. The structure and the absence of signs of free or hindered rotation, can be accounted for by hydrogen bonding between the proton and the ring oxygen.

Mikrowellenspektrum, Struktur und Dipolmoment von Trichiorsilan und Methyltrichlorsilan

1967 ◽  
Vol 22 (9) ◽  
pp. 1415-1418 ◽  
Author(s):  
M. Mitzlaff ◽  
R. Holm ◽  
H. Hartmann
Keyword(s):  
Dipole Moment ◽  
Internal Rotation ◽  
Structural Parameters ◽  
Rotational Spectrum ◽  
Centrifugal Distortion ◽  
Rotational Constants ◽  
Isotopic Species ◽  
Quadrupole Coupling

The rotational spectrum of several isotopic species of HSiCl3 and CH3SiCl3 was studied in the region from 8 to 40 Gc. From the derived rotational constants the following structural parameters were obtained using KRAITCHMAN'S equations:dSi-H= (1.4655±0.0002) A, dSi-Cl= (2.0118±0.0009) A, ∢ Cl—Si—Cl= (110,60±0.25)°.Furthermore the constants for centrifugal distortion DJ= (1.2 ± 0.4) kc for HSiCl3 and DJ= (0.19 ± 0.04) kc for CH3SiCl3, for the quadrupole coupling e Q Vzz= + 12.8 Mc and the dipole moment μ= (0.86 ± 0.01) D for HSiCl3 and μ= (1.91 ± 0.01) D for CH3SiCl3 were determined. The interaction of the overall-rotation with the internal rotation is discussed for CH3SiCl3, and the hindering barrier is estimated to be less than 200 cm-1.

Mikrowellenspektrum, Rotationskonstanten, Zentrifugalverzerrungskonstanten und Kernquadrupolkopplungskonstanten des CD3SiH2Cl. Über Bindungseigenschaften in Silicium-Halogeniden: 1. Mitteilung / Microwave spectrum, rotational constants, centrifugaldistortion constants and nuclear quadrupole coupling constants of CD3SiH2Cl

1972 ◽  
Vol 27 (7) ◽  
pp. 1150-1159 ◽  
Author(s):  
Werner Zeil ◽  
Richard Gegenheimer ◽  
Saskia Pferrer ◽  
Marwan Dakkouri
Keyword(s):  
Microwave Spectrum ◽  
Coupling Constants ◽  
Rotational Constants ◽  
Microwave Spectra ◽  
Isotopic Species ◽  
Quadrupole Coupling ◽  
Nuclear Quadrupole

Abstract Microwave The microwave spectra of the following isotopic species of methylchloro-silane CD328SiH235Cl, CD329SiH235Cl, CD330SiH235Cl, CD328SiH237Cl have been measured and analyzed. The rotational constants, centrifugaldistortion constants and nuclear quadrupole coupling constants have been determined. The Si-Cl-distance is 2.049 Å respectively 2.052 Å as calculated by the rs method. The corresponding angles between the siliconchlorine-bond and the inertia-axis a are Θ = 26°53' respectively 26°49'

Mikrowellenspektrum, interne Rotation, Struktur und Dipolmoment von Methylchloroform

1968 ◽  
Vol 23 (2) ◽  
pp. 307-311
Author(s):  
R. Holm ◽  
M. Mitzlaff ◽  
H. Hartmann
Keyword(s):  
Dipole Moment ◽  
Stark Effect ◽  
Equilibrium Configuration ◽  
Structural Parameters ◽  
Microwave Spectrum ◽  
Methyl Group ◽  
Intensity Measurements ◽  
Isotopic Species ◽  
Asymmetric Top ◽  
Torsional Isomers

The microwave spectrum of several symmetric and asymmetric top isotopic species of CH3CCl3 has been studied in the region from 8 to 40 GHz. A least squares analysis of the rotational con-stants gave the following structural parameters :dC-C =(1.541 ±0.001) A, dC-Cl = (1,7712 ± 0.0008) A, dC-H = (1.090 ± 0.002) A, ∢H—C—H= (110.04±0.25) ° , ∢Cl—C—Cl= (109.39 ±0.25) ° .A dipole moment of μ = (1.755 ± 0.015) D has been derived from the investigation of the Stark effect of the transition J=4→5 of CH3CCl3335. From intensity measurements the barrier to internal rotation is estimated to be (1740 ± 300) cal/mol. An analysis of the spectrum of CH2DCCl2Cl37 shows conclusively that methylchloroform in its equilibrium configuration has the methyl group staggered with respect to the CCl3-group. It could be shown that there exist two torsional isomers gauche and anti with specific microwave spectra.

Mikrowellenspektrum, rotationsspektroskopische Konstanten und r0-Struktur des CSFCl / Microwave Spectrum, Spectroscopic Constants and r0 Structure of CSFCl

1975 ◽  
Vol 30 (2) ◽  
pp. 183-194 ◽  
Author(s):  
Hans Joachim Kohrmann ◽  
Werner Zeil
Keyword(s):  
Microwave Spectrum ◽  
Spectroscopic Constants ◽  
Structure Parameters ◽  
Centrifugal Distortion ◽  
Rotational Constants ◽  
Microwave Spectra ◽  
Isotopic Species ◽  
Centrifugal Distortion Constants

Abstract The microwave spectra of following isotopic species 12. 12C32S19F35Cl, 12C32S19F37Cl, 12C34S19F35Cl, 13C32S19F35Cl have been measured. The rotational constants and the centrifugal distortion constants have been determined and a r0 structure calculated. The structure parameters are: rCS 1.595° Å, rCF 1.326° Å, rCCl 1.715° Å, ∢ SCF 123.82°, SCCl 127.12°.

The microwave spectrum, dipole moment, and structure of cyclopropyl carbinol

1970 ◽  
Vol 48 (19) ◽  
pp. 2949-2954 ◽  
Author(s):  
A. Bhaumik ◽  
W. V. F. Brooks ◽  
S. C. Dass ◽  
K. V. L. N. Sastry
Keyword(s):  
Hydrogen Bonding ◽  
Dipole Moment ◽  
Dipole Moments ◽  
Microwave Spectrum ◽  
Rotational Constants ◽  
Rotational Isomers ◽  
Microwave Spectra ◽  
Strained Bonds ◽  
Hydroxyl Hydrogen

The microwave spectra of cyclopropyl carbinol [Formula: see text] and its deuterated (—OD) form were studied in the region of 8 to 35 gHz. Only one of the possible rotational isomers was identified. The measured rotational constants and dipole moments for C3H5CH2OH and C3H5CH2OD are, respectively, A (mHz): 12485.13, 12064.04; B (mHz): 3236.46, 3177.22; C (mHz): 2894.38, 2826.19; κ: −0.928665, −0.924001; μa (D): 1.81, 1.78; μb (D): 0.36, 0.32; μc (D): 0.31, 0.30; μtotal(D): 1.87, 1.84.Rotation is apparently hindered by hydrogen bonding between the hydroxyl hydrogen and the electrons in the strained bonds of the cyclopropyl ring.

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