Molecular g-Values, Magnetic Susceptibility Anisotropics and Molecular Electric Quadrupole Moment of Methylenecyclobutenone

1974 ◽  
Vol 29 (12) ◽  
pp. 1820-1826 ◽  
Author(s):  
W. Czieslik ◽  
D. H. Sutter
Keyword(s):  
Experimental Data ◽  
Magnetic Susceptibility ◽  
Quadrupole Moment ◽  
Zeeman Effect ◽  
Electric Quadrupole ◽  
Quadrupole Moments ◽  
Electric Quadrupole Moment ◽  
Ring Molecules ◽  
Indo Calculations ◽  
Additivity Rules

The rotational Zeeman-effect of methylenecyclobutenone has been investigated giving the molecular (g-values: gaa = -0.0925 ± 0.0003, gbb = -0.0729 ±0.0003, gcc = -0.0086 ± 0.0003 and the magnetic susceptibility anisotropies: 2χaa-χbb-χcc= (23.0 ± 0.5) · 10-6 erg/G2 mole and 2χbb-χcc-χaa= (25.5 ± 0.5) · 10-6 erg/G2 mole. These values correspond to the following molecular electric quadrupole moments given in units of 10-28 esu cm2: Qaa = 1.0±0.6, Qbb= 2.8±0.6 and Qcc = 3.8± 1.0. The experimental data of methylenecyclobutenone and similar strained ring molecules are compared with the results of INDO-calculations and values obtained from additivity rules for bond contributions.

scholarly journals The Rotational Zeeman Effect in Fluorobenzene and the Molecular Quadrupole Moment in Benzene

1982 ◽  
Vol 37 (10) ◽  
pp. 1165-1175 ◽  
Author(s):  
W. H. Stolze ◽  
M. Stolze ◽  
D. Hübner ◽  
D. H. Sutter
Keyword(s):  
Magnetic Susceptibility ◽  
Carbon Tetrachloride ◽  
Quadrupole Moment ◽  
Ring Current ◽  
Zeeman Effect ◽  
Electric Quadrupole ◽  
Quadrupole Moments ◽  
Electric Quadrupole Moment ◽  
Microwave Spectrometer ◽  
Out Of Plane

The rotational Zeeman effect in fluorobenzene is reinvestigated with a resolution improved by a factor of almost five to give more accurate g-tensor elements, magnetic susceptibility anisotropics and molecular electric quadrupole moments. The results fit into the pictures of a linear dependence of the out of plane molecular electric quadrupole moment, Qcc, on the number of fluorine substituents and of a linear correlation between the nonlocal (ring current) susceptibility, Χccnonlocal, and the CNDO/2-π-electron density alternation. They lead to a gasphase molecular electric quadrupole moment in benzene, Qcc,benzene = - (28.4 ± 4.7) · 10-40 Cm2 which is slightly less negative than the value deduced from electric field-gradient birefringence experiments on dilute benzene solutions with carbon tetrachloride as solvent. A detailed description of the high resolution microwave spectrometer is given in the appendix.

The Rotational Zeeman Effect in Acetone, its g-Tensor, its Magnetic Susceptibility Anisotropics and its Molecular Electric Quadrupole Moment Tensor; A High Resolution Microwave Fourier Transform Study

1992 ◽  
Vol 47 (3) ◽  
pp. 527-532 ◽  
Author(s):  
Frank Oldag ◽  
Dieter H. Sutter
Keyword(s):  
Magnetic Susceptibility ◽  
Fourier Transform ◽  
Quadrupole Moment ◽  
Moment Tensor ◽  
Zeeman Effect ◽  
Electric Quadrupole ◽  
Effect Study ◽  
Rigid Rotor ◽  
Electric Quadrupole Moment ◽  
Asymmetric Top

Abstract Acetone is a molecule with an intermediate barrier for methyl- top internal rotation, and only molecules in the A1A1 - state of the tunneling motion exhibit a rigid rotor spectrum. For this state we report the results of a rotational Zeeman effect study of acetone in exterior fields up to 20 kGauss (2 Tesla). From an analysis of the observed Zeeman splittings within the asymmetric top approximation the nonzero elements of the g-tensor and the magnetic susceptibility anisotropies were obtained as follows: gaa= -0.04379 (8), gbb = - 0.06611 (5), gcc=-O.O1481 (7), 2ξaa -ξbb - ξcc = - 9.53 (21) 10-6 erg G -2 mole-1 and 2 ξbb - ξcc - ξaa = 25.57 (18) 10-6 erg G -2 mole-1 . The nonzero elements of the molecular electric quadrupole moment tensor were derived as Qaa- 2-77 (13) DÅ, Qbb= -4.59 (10) DÅ and Qcc= 1.82 (15) DÅ. Zeeman spectra were also recorded for seveal low-J transitions of molecules in the EE-state of methyl top tunneling (one top tunneling), and so far the same splittings have been found as for the A1 A1-species

scholarly journals The Molecular Zeeman Effect of Norbornadiene, its g-Values, Magnetizability Anisotropics, and Molecular Electric Quadrupole Moment; A High-Resolution Microwave Fourier-Transform Study Combined with Quantum Chemical Calculations

1998 ◽  
Vol 53 (1-2) ◽  
pp. 67-76 ◽  
Author(s):  
K. Voges ◽  
D. H. Sutter ◽  
K. Ruud ◽  
T. Helgaker
Keyword(s):  
Gas Phase ◽  
Quadrupole Moment ◽  
Equilibrium Configuration ◽  
Moment Tensor ◽  
Zeeman Effect ◽  
Electric Quadrupole ◽  
Quadrupole Moments ◽  
Electric Quadrupole Moment ◽  
Atomic Orbitals ◽  
Experimental Findings

Abstract The molecular Zeeman effect is reported for norbornadiene at fields near 18 kG. The experimental results are for the molecular g-values: gaa = 0.02860(16), gbb = 0.05271(11), gcc = 0.00142(26), for the magnetizability anisotropics: 2ξaa - ξbb - ξcc = -0.41(26) · 10-6 ergG-2 mol-1 , 2ξbb - ξcc - ξaa = +40.72(27) · 10-6 erg G-2 mol-1 and for the molecular electric quadrupole moments: Qaa = -1.78(20) · 10 -26 esu cm2 , Qbb = 3.73(20) · 10-26 esu cm2 , Qcc = -1.94(30) · 10-26 esu cm2 , with the c-axis of the molecular inertia tensor aligned to the C2v-axis of the equilibrium configuration. The results of ab-initio calculations, using London type atomic orbitals as basis functions, are reported for the g-tensor, the magnetizability tensor and the molecular electric quadrupole moment tensor and are compared to the experimental findings. The possibilities of strain induced magnetizability exaltations and of systematic differences between gas phase and bulk phase magnetizabilities are discussed.

scholarly journals The Molecular Zeeman Effect of Imines. I. Methanimine, its Molecular g-Tensor, its Magnetic Susceptibility Anisotropies, its Molecular Electric Quadrupole Moment, its Electric Field Gradient at the Nitrogen Nucleus, and its Nitrogen Spin-Rotation Coupling

1989 ◽  
Vol 44 (11) ◽  
pp. 1063-1078 ◽  
Author(s):  
H. Krause ◽  
D. H. Sutter
Keyword(s):  
Magnetic Susceptibility ◽  
Zeeman Effect ◽  
Electric Quadrupole ◽  
Spin Rotation ◽  
Coupling Constants ◽  
Zero Field ◽  
Quadrupole Moments ◽  
Magnetic Susceptibility Tensor ◽  
State Expectation ◽  
The Individual

Abstract The rotational Zeeman effect has been observed in methanimine which was produced from ethylenediamine by flash pyrolysis. The observed vibronic ground state expectation values of the molecular g-values, the magnetic susceptibility anisotropies and the molecular electric quadrupole moments are: gaa = -1.27099(22), gbb= -0.18975(7), gcc= -0.03440(8), 2ξaa-ξbb-ξcc = 12.49(19) · 10-6 ergG-2mol-1, 2ξbb-ξcc-ξaa = 5.22(11) · 10-6 ergG-2 mol-1 Qaa = 0.43(17) · 10-26esu cm2, Qbb= 1.08(10) · 10-26 esu cm2, and Qcc= -1.51 (26) . 10-26 esu cm2. With the TZVP ab initio value for the out-off plane electronic second moment as additional input, reliable values can be given also for the individual components of the magnetic susceptibility tensor and for the bulk susceptibility:ξ = (ξaa + ξbb + ξcc)/3=-13.13(88) · 10-6 erg G -2 mol-1. From low-J a-and b-type zero field transitions the spin-rotation coupling constants and the 14N nuclear quadrupole coupling constants could be redetermined with improved accuracy. These data are compared with our new theoretical results.

The 14N Nuclear Quadrupole Coupling Tensors, the Tensors of the Molecular Magnetic Susceptibility and the Molecular Electric Quadrupole Moment in Pyrazole: A High Resolution Rotational Zeeman Effect Study

1990 ◽  
Vol 45 (11-12) ◽  
pp. 1248-1258 ◽  
Author(s):  
O. Böttcher ◽  
D. H. Sutter
Keyword(s):  
Magnetic Susceptibility ◽  
High Resolution ◽  
Quadrupole Moment ◽  
Moment Tensor ◽  
Electric Quadrupole ◽  
Coupling Constants ◽  
Zero Field ◽  
Electric Quadrupole Moment ◽  
Magnetic Susceptibility Anisotropy ◽  
Quadrupole Coupling

AbstractHigh resolution zero field and Zeeman rotational spectra of 1 D-pyrazole have been studied by microwave Fourier-transform spectroscopy. The zero field hfs patterns allowed to improve the quadrupole coupling constants for both 14N nuclei. From the high field Zeeman multiplets the diagonal elements of the g-tensor were obtained as gaa= -0.1178(2),.gbb=-0.0762(2) and gcc = 0.0608 (2). The two independent components of the molecular magnetic susceptibility anisotropy in units of 10-6 erg G-2 mole- 1 are 2 ξaa - ξbb - ξcc= 52.69(32) and 2 ξbb - ξcc - ξaa = 39.32(29) were, a, b, c denote the molecular principal inertia axes. From these values the components of the molecular electric quadrupole moment tensor in units of 10-26 esu cm2 follow as Qaa = 5.84(22), Qbb= -0.58 (21) and Qcc= -5.27(38). Comparison with corresponding values for the undeuterated species leads to the complete tensors including their orientation with respect to the nuclear frame.

Molecular g-Values, Magnetic Susceptibility Anisotropics, Second Moments of the Charge Distribution, and Molecular Electric Quadrupole Moments in trans- and cis-Thioformic Acid

1978 ◽  
Vol 33 (1) ◽  
pp. 29-37 ◽  
Author(s):  
G. K. Pandey ◽  
D. H. Sutter
Keyword(s):  
Magnetic Susceptibility ◽  
Charge Distribution ◽  
Zeeman Effect ◽  
Electric Quadrupole ◽  
Covalent Bonding ◽  
Microwave Spectrum ◽  
Quadrupole Moments ◽  
Second Moments ◽  
In Trans ◽  
Single Standard

The rotational Zeeman effect in the microwave spectrum of trans- and cis-Thioformic Acid has been investigated at field strengths upto 25.6 kG. Measurements were done for both ⊿M = 0 and ⊿M = ± 1 selection rules for the trans species and for ⊿M = ±1 for the cis species. From the observed splittings the following parameters were obtained for the diagonal elements of the molecular g tensor and the susceptibility anisotropics.(all experimental uncertinties are single standard deviations).The molecular electric quadrupole moments derived from the Zeeman data indicate that there is no significant covalent bonding in the O…H region of the trans species.

NUMBER-PROJECTED ELECTRIC QUADRUPOLE MOMENTS OF EVEN–EVEN PROTON-RICH NUCLEI IN THE ISOVECTOR PAIRING CASE

2013 ◽  
Vol 22 (05) ◽  
pp. 1350029 ◽  
Author(s):  
M. DOUICI ◽  
N. H. ALLAL ◽  
M. FELLAH ◽  
N. BENHAMOUDA ◽  
M. R. OUDIH
Keyword(s):  
Quadrupole Moment ◽  
Mean Field ◽  
Electric Quadrupole ◽  
Variation Method ◽  
Quadrupole Moments ◽  
Electric Quadrupole Moment ◽  
Pairing Effect ◽  
Before And After ◽  
Projection Effect ◽  
Gap Parameter

An expression of the number-projected electric quadrupole moment Q2 has been established in the isovector pairing case using the SBCS discrete projection before variation method. It has been verified that this expression reduces to the pairing between like-particles one at the limit when the np pairing gap parameter Δ np goes to zero. The convergence of the projection method has been numerically tested and a fast convergence has been observed. The electric quadrupole moment has been numerically calculated for some even–even proton-rich nuclei such as 16 ≤ Z ≤ 56 and 0 ≤ (N-Z) ≤ 4. The single-particle energies and eigen-states used are those of a Woods–Saxon mean-field. The np pairing effect on Q2 has been studied either before and after the projection; it seems that it is somewhat small since the relative discrepancies do not exceed 12%. Moreover, the np pairing effect is roughly the same in both situations. However, it has been shown that this effect diminishes with increasing values of (N-Z). The projection effect on Q2 has also been studied when including, or not, the np pairing correlations. It appears that this effect is slightly less important in the np pairing case than when only the pairing between like-particles is considered.

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