Phase transition and temperature effects in m�ssbauer and NMR spectra [N(CH3)3H]2SnF6 crystals

1977 ◽  
Vol 18 (2) ◽  
pp. 213-216 ◽  
Author(s):  
V. A. Varnek ◽  
S. P. Gabuda ◽  
B. I. Obmoin
Keyword(s):  
Phase Transition ◽  
Temperature Effects ◽  
Nmr Spectra

Pressure and temperature effects on the phase transition from a dense droplet to a lamellar structure in a ternary microemulsion

2000 ◽  
Vol 112 (23) ◽  
pp. 10608-10614 ◽  
Author(s):  
Hideki Seto ◽  
Daisuke Okuhara ◽  
Youhei Kawabata ◽  
Takayoshi Takeda ◽  
Michihiro Nagao ◽  
...  
Keyword(s):  
Phase Transition ◽  
Temperature Effects ◽  
Lamellar Structure ◽  
Pressure And Temperature Effects

Pressure and Temperature Effects on the Raman Spectra of Aqueous Micellar Solutions of Sodium Oleate

1983 ◽  
Vol 22 ◽  
Author(s):  
P.T.T. Wong ◽  
H.H. Mantsch
Keyword(s):  
Phase Transition ◽  
Sodium Oleate ◽  
Temperature Effects ◽  
Micellar Solution ◽  
Room Temperature ◽  
Structural Changes ◽  
Micellar Solutions ◽  
Micellar Phase ◽  
Aqueous Micellar Solutions ◽  
Pressure And Temperature Effects

Sodium oleate is practically insoluble in water at room temperature. Yet, when heated above the critical micellization temperature (cmt), its solubility increases rapidly and an isotropic optically clear micellar solution is formed. Upon cooling below the critical coagelization temperature (cct), the micellar phase transforms to an opaque curd, the coagel phase. The structural changes and the nature of this phase transition are, however, not well characterized.

scholarly journals Study of Structural Phase Transitions in [Mg(H2O)6][SiF6] by Means of Single Crystal 2H NMR

2002 ◽  
Vol 57 (6-7) ◽  
pp. 408-412 ◽  
Author(s):  
Takahiro Iijima ◽  
Motohiro Mizuno ◽  
Masahiko Suhara ◽  
Kazunaka Endo
Keyword(s):  
Phase Transition ◽  
Single Crystal ◽  
Nmr Spectra ◽  
Structural Phase ◽  
Water Molecules ◽  
2H Nmr ◽  
Structural Phase Transitions ◽  
H Nmr ◽  
Rotational Modulation ◽  
Infinite Temperature

The temperature and angular dependences of 2H NMR spectra were measured for single crystal of [Mg(H2O)6][SiF6]. At 283 K, (e2Qq/h,η) of 2H, averaged by fast 180° flip of water molecules, were obtained as (128 kHz, 0.72), (123 kHz, 0.82) and (106 kHz, 0.80), corresponding to three unequal water molecules in [Mg(H2O)6]2+. At 338 K, (e2Qq/h,η) averaged further by the fast reorientation of [Mg(H2O)6]2+ around the 3 axis was obtained as (57 kHz, 0.01). In phase II, the jumping rate for the reorientation ( ) and the amplitude of the rotational modulation (Δ ) of [Mg(H2O)6]2+ about the C3 axis were obtained from the simulation of 2H NMR spectra. The jumping rate at infinite temperature and the activation energy were estimated from the temperature dependence of k as k0 = 9 1017 s-1 and a = 78 kJmol-1, respectively. The II-III phase transition was found to be related with the freeze of this motion

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