화학공학소재연구정보센터
Chemical Physics Letters, Vol.401, No.4-6, 368-373, 2005
Static and dynamic studies on cycloheptanol as two-orientational glass-former
Two-orientational glass transitions of two different orientationally disordered states of cycloheptanol are investigated and compared through static (thermodynamic and X-ray diffraction) as well as dynamic (dielectric spectroscopy) experimental techniques. What makes cycloheptanol unique is that one of these disordered states presents an isotropic lattice while for the other the lattice is anisotropic and the orientational glass transition temperature of the anisotropic-glassy state is found to be higher than that of the isotropic one. This result is discussed through the fragility concept, being consistent with the Adam-Gibbs theory. In addition, the kinetic fragilities through (F-1/2-metric) as well as the thermodynamic fragilities through ((DeltaT(gl)/ T-gl(A))-metric) of both states seem also to correlate in a consistent way. (C) 2004 Elsevier B.V. All rights reserved.