scholarly journals Temperature Dependences of the Nuclear Quadrupole Resonance Frequencies in 1,4-Dihalogenocyclohexanes

1962 ◽  
Vol 35 (8) ◽  
pp. 1293-1299 ◽  
Author(s):  
Tadashi Tokuhiro
Keyword(s):  
Nuclear Quadrupole Resonance ◽  
Resonance Frequencies ◽  
Quadrupole Resonance ◽  
Temperature Dependences ◽  
Nuclear Quadrupole

Nuclear quadrupole resonance and intermolecular interactions: temperature and pressure effects in Group V trichlorides

1976 ◽  
Vol 54 (14) ◽  
pp. 2266-2279 ◽  
Author(s):  
Grant Callum Gillies ◽  
Richard Julian Challis Brown
Keyword(s):  
Nuclear Quadrupole Resonance ◽  
Pressure Coefficient ◽  
Pressure Effects ◽  
Group V ◽  
Resonance Frequencies ◽  
Quadrupole Resonance ◽  
Temperature Dependences ◽  
Intermolecular Bonding ◽  
Temperature And Pressure ◽  
Nuclear Quadrupole

Nuclear quadrupole resonance frequencies for the metal and chlorine atoms in AsCl3 and SbCl3 have been measured as functions of temperature and pressure. These data are analysed to obtain the isothermal volume dependences and the isochoric temperature dependences of the field gradient parameters. Existing knowledge of the Group V trichlorides shows that the strength of intermolecular bonding increases in the order AsCl3 < SbCl3 < BiCl3, and this trend is reflected in the relative importance of volume effects in determining the nqr frequencies in these solids. A simple theory of the pressure dependences of nqr frequencies in molecular crystals is proposed, which accounts for all data presently available. The pressure coefficient contains static and dynamic contributions which are of opposite signs; the static contribution is negative and becomes numerically larger as the strength of intermolecular bonding increases.

The 35Cl nuclear quadrupole resonance spectra of BCl3 and several of its amine and nitrile complexes

1970 ◽  
Vol 48 (5) ◽  
pp. 697-704 ◽  
Author(s):  
M. Kaplansky ◽  
M. A. Whitehead
Keyword(s):  
Nuclear Quadrupole Resonance ◽  
Molecular Orbital ◽  
Amine Complexes ◽  
Resonance Frequencies ◽  
Quadrupole Resonance ◽  
Temperature Dependences ◽  
Nuclear Quadrupole ◽  
35Cl Nuclear Quadrupole Resonance

The 35Cl nuclear quadrupole resonance frequencies of BCl3, two amine complexes, and five nitrile complexes of BCl3 are reported for 77 °K. Two molecular orbital theories, BEEM-π and CNDO, are used to interpret the frequencies.The temperature dependences of the 35Cl nuclear quadrupole resonance frequencies of B-trichloroborazole are reported.

scholarly journals Rapid Survey of Nuclear Quadrupole Resonance by Broadband Excitation with Comb Modulation and Dual-Mode Acquisition

2020 ◽  
Author(s):  
Yuta Hibe ◽  
Yasuto Noda ◽  
K. Takegoshi ◽  
Kazuyuki Takeda
Keyword(s):  
Nuclear Quadrupole Resonance ◽  
Frequency Comb ◽  
Spin Dynamics ◽  
Signal Acquisition ◽  
Dual Mode ◽  
Rapid Scan ◽  
Resonance Frequencies ◽  
Wide Range ◽  
Quadrupole Resonance ◽  
Nuclear Quadrupole

Nuclear Quadrupole Resonance (NQR) provides spectra carrying information as to the electric-field gradient around nuclei with a spin quantum number I > 1/2 and offers helpful clues toward characterizing the electronic structure of materials of chemical interest. A major challenge in NQR is finding hitherto unknown resonance frequencies, which can scatter over a wide range, requiring time consuming repetitive measurements with stepwise frequency increments. Here, we report on an efficient, two-step NQR protocol by bringing rapid-scan and frequency-comb together. In the first step, wideband excitation and simultaneous signal acquisition, both realized by a non-adiabatic, frequency-swept hyperbolic secant (HS) pulse with comb modulation, offers a clue for the existence/absence of the resonance within the frequency region under investigation. When and only when the sign of the resonance has been detected, the second step is implemented to compensate the limited detection bandwidth of the first and to unambiguously determine the NQR frequency. We also study the spin dynamics under the comb-modulated HS pulse by numerical simulations, and experimentally demonstrate the feasibility of the proposed scheme, which is referred to as RApid-Scan with GApped excitation with Dual-mode Operation (RASGADO) NQR<br>

Nuclear Quadrupole Resonance Studies of Chelated Antimony Complexes. Part III. The Carboxylates: RCO2SbCl4

1986 ◽  
Vol 41 (1-2) ◽  
pp. 179-185
Author(s):  
Claudine Gerard-Dion ◽  
Joyce Rupp-Bensadon ◽  
Edwin A. C. Lucken
Keyword(s):  
Phase Change ◽  
Nuclear Quadrupole Resonance ◽  
Chlorine Atoms ◽  
Resonance Frequencies ◽  
Quadrupole Resonance ◽  
Antimony Complexes ◽  
Quantitative Basis ◽  
Nuclear Quadrupole ◽  
The Difference

The 35Cl, 121Sb and 123Sb resonance frequencies for seventeen tetrachloro(carboxylato)antimony V compounds, RCO2SbCl4, are reported. The results confirm the difference in the effects of the substituent on the equatorial chlorine atoms and the axial chlorine atoms of the SbCl4 group, previously remarked in Parts I and II of this series, and this effect has been put on a more quantitative basis by correlating the observed frequencies with the pK’s of the corresponding acids.The compounds with R = isopropyl and R = cyclopropyl both show a phase change in the region of 140 K which may correspond to reorientation of the substituent about the R - CO2 axis.

Nuclear Quadrupole Resonance in Chloro- and Bromoantimonate(III) Complexes

1986 ◽  
Vol 41 (1-2) ◽  
pp. 319-325 ◽  
Author(s):  
Tsutomu Okuda ◽  
Nobuhiko Tanaka ◽  
Sumio Ichiba ◽  
Koji Yamada
Keyword(s):  
Nuclear Quadrupole Resonance ◽  
Quadrupole Resonance ◽  
Temperature Dependences ◽  
Nuclear Quadrupole

C1,3581Br, and 121Sb N Q R spectra were observed in com plexes o f the type RxSbyX z with anionstoichiometries SbCl4 , SbClg- , SbBr4 , SbBr^~, SbBr^- , and Sb2Br^~. Several complexes showwidely spaced halogen resonance lines and unusual temperature dependences o f the NQ Rfrequencies. These findings are accounted for

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