NMR line-width, self-diffusion and relaxation studies of neopentanol in liquid and solid phases

被引:3
作者
Aksnes, DW
Kimtys, L
机构
[1] Univ Bergen, Dept Chem, N-5007 Bergen, Norway
[2] Vilnius State Univ, Dept Phys, LT-2734 Vilnius, Lithuania
关键词
NMR spectroscopy; relaxation; self-diffusion; neopentanol;
D O I
10.1016/S0022-2860(97)00218-4
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
The translational and rotational dynamics of the liquid and disordered (solid I) phases of neopentanol are investigated using high-field multinuclear NMR. The extensive line-narrowing of the H-1 resonances for solid I is ascribed to the onset of translational diffusion whereas the line-narrowing of the deuteron and carbon-13 signals is dominated by molecular reorienta tions. The activation energy of the molecular self-diffusion is 34 and 71 kJ mol(-1) for the liquid and solid I phases, respectively. The self-diffusion coefficient of solid I is 3.2 x 10(-13) m(2) s(-1) at the melting point. A thorough analysis of the multinuclear T-1 data is presented. The activation energy of the overall tumbling motion in the liquid and solid I phases, obtained from the hydroxyl deuteron T-1 data, is 36 and 52 kJ mol(-1), respectively. The internal reorientations have a profound effect on the spin-lattice relaxation times of the methyl and methylene groups by reducing the effective correlation time by an order of magnitude relative to the overall tumbling motion in solid I. The long correlation time (22 and 58 ps of liquid and solid neopentanol at the melting point) and high activation energy suggest that the overall tumbling motion in the liquid and disordered phases involves hydrogen-bonded aggregates. (C) 1998 Elsevier Science B.V.
引用
收藏
页码:25 / 33
页数:9
相关论文
共 28 条
[11]   DIELECTRIC CONSTANT OF HYDROGEN-BONDED LIQUIDS .4. EQUILIBRIUM AND RELAXATION STUDIES OF HOMOLOGOUS NEO-ALCOHOLS [J].
DANNHAUS, W ;
BAHE, LW ;
LIN, RY ;
FLUECKIN, AF .
JOURNAL OF CHEMICAL PHYSICS, 1965, 43 (01) :257-+
[12]   ROTATIONAL TRANSITIONS IN NEOPENTYL ALCOHOL AND NEOPENTYL GLYCOL [J].
FAUCHER, JA ;
GRAHAM, JD ;
KOLESKE, JV ;
SANTEE, ER ;
WALTER, ER .
JOURNAL OF PHYSICAL CHEMISTRY, 1966, 70 (11) :3738-&
[13]   A NUCLEAR MAGNETIC RESONANCE STUDY OF HYDROGEN BONDING IN HYDROXYLIC COMPOUNDS [J].
FEENEY, J ;
WALKER, SM .
JOURNAL OF THE CHEMICAL SOCIETY A -INORGANIC PHYSICAL THEORETICAL, 1966, (09) :1148-&
[14]   MOLECULAR MOTIONS IN LIQUID .1. ROTATION OF WATER AND SMALL ALCOHOLS STUDIED BY DEUTERON RELAXATION [J].
FUNG, BM ;
MCGAUGHY, TW .
JOURNAL OF CHEMICAL PHYSICS, 1976, 65 (08) :2970-2976
[15]   MOLECULAR MOTIONS IN 2-IODO-2-METHYLPROPANE, (CH3)3CI - PROTON NUCLEAR MAGNETIC-RESONANCE MEASUREMENTS AT VARIABLE TEMPERATURES [J].
HASEBE, T ;
STRANGE, JH ;
CHEZEAU, JM .
JOURNAL OF THE CHEMICAL SOCIETY-FARADAY TRANSACTIONS II, 1988, 84 :885-892
[16]   NMR PULSED-GRADIENT DIFFUSION MEASUREMENTS .1. SPIN-ECHO STABILITY AND GRADIENT CALIBRATION [J].
HROVAT, MI ;
WADE, CG .
JOURNAL OF MAGNETIC RESONANCE, 1981, 44 (01) :62-75
[17]   GLASS-TRANSITION AND SECONDARY RELAXATIONS IN MOLECULAR LIQUIDS AND CRYSTALS [J].
JOHARI, GP .
ANNALS OF THE NEW YORK ACADEMY OF SCIENCES, 1976, 279 (OCT15) :117-140
[18]  
Karger J., 1988, Adv. Magn. Reson, V12, P1
[20]   X-RAY DIFFRACTION STUDY OF CRYSTALLINE NEOPENTANE (TETRAMETHYL METHANE) [J].
MONES, AH ;
POST, B .
JOURNAL OF CHEMICAL PHYSICS, 1952, 20 (04) :755-756