Zobrazeno 1 - 10
of 51
pro vyhledávání: '"B. A. DUNELL"'
Autor:
T. T. Ang, B. A. Dunell
Publikováno v:
Canadian Journal of Chemistry. 54:1985-1990
Spin–lattice relaxation times of tetramethylphosphonium chloride, bromide, and iodide were measured between 100 and 500 K and the two minima in T1 found for each compound have been assigned to methyl group reorientation and whole cation tumbling. T
Publikováno v:
Journal of Magnetic Resonance (1969). 67:217-230
The intensities of peaks in spinning sidebands relative to those of the central band in magic angle spinning NMR spectra have been used in a graphical method of Herzfeld and Berger to determine the principal components of each of the two chemical shi
Publikováno v:
Journal of Magnetic Resonance (1969). 32:391-402
Proton spin-lattice relaxation times have been measured at 16, 31, and 59 MHz in 4-methyl-2,6-ditertiarybutyl phenol between 80 K and its melting point, 340 K. The variation of T1 with temperature shows too distinct minima. The lower-temperature mini
Autor:
B. A. Dunell, Christopher I. Ratcliffe
Publikováno v:
J. Chem. Soc., Faraday Trans. 2. 77:2169-2180
Spin–lattice relaxation times, T1, have been measured over appropriate temperature ranges for sulphamic acid (NH3SO3), caesium trifluoromethanesulphonate (CF3SO3Cs) and caesium methanesulphonate (CH3SO3Cs). Reorientation about the C3v axis of the t
Publikováno v:
Journal of Magnetic Resonance (1969). 60:486-489
For many materials 13C NMR lines obtained in solid and solution states differ by no more than a few ppm; however, when many lines are closely spaced, direct correlation between solid and solution lines is impossible. Although many t~c~~i~~e§ exist f
Autor:
Christopher I. Ratcliffe, B. A. Dunell
Publikováno v:
J. Chem. Soc., Faraday Trans. 2. 77:2181-2189
Proton spin–lattice relaxation times have been studied in para-toluenesulphonic acid hydrate, CH3C6H4SO3–H3O+, as a function of temperature between 80 K and its melting point. Two relaxation processes occur which have been attributed to three-fol
Autor:
J. A. Ripmeester, B. A. Dunell
Publikováno v:
Canadian Journal of Chemistry. 52:191-197
The adiabatic rapid passage (ARP) technique was applied to the study of molecular motion in solids. Second moments and spin–lattice relaxation times for solid furan and benzene were derived using ARP methods from 77 °K to the respective melting po
Autor:
B. A. Dunell, T. T. Ang
Publikováno v:
Canadian Journal of Chemistry. 52:1840-1847
The spin–lattice relaxation times of the solid complexes of trimethylamine with I2, ICl, Br2, BCl3, and BBr3 and the relaxation null times of trimethylphosphine – boron trichloride and – boron tribromide have been measured over a range of tempe
Autor:
B. A. Dunell, T. T. Ang
Publikováno v:
J. Chem. Soc., Faraday Trans. 2. 75:169-177
Tetramethylarsonium chloride, bromide and iodide have been prepared and their spin–lattice relaxation times measured by proton magnetic resonance pulse spectrometry in the temperature range 77–540 K. The two minima in T1 found for each salt have
Publikováno v:
Molecular Physics. 34:241-249
The 19F nuclear resonance spectra and spin-lattice relaxation times have been observed in solid PF3 over the temperature range 77 K to its melting point at 121·8 K. Within this temperature range PF3 exists in three crystallographic phases. Phase I i