k c e i v d 18 Sepiember 1992 Abslmel. Raman specm of he two-dimensional antiferromagnet hfnPSe3 are measured in the temperature region between 18 and 297 K. Below T, = 14 f 2 K an anomalous enhancement 01 some Raman-aaive phonon p b h observed. A new phonon peak appears below T, at I a n -I . me relation between its behaviour and Qe magnelic ordering is explained in terms of (lie spin-dependenl phonon Raman pmc?s. A peak at 133 a n -I (T = 18 K) shifts 10 low liequency with increasing Iemperature and disappeals above TN. I1 is assigned to a one-magnon Raman peak.

The zero-field critical temperature and the coherence length in the layered superconductor 2H-NbSe2-xSx (x=O-2.0) were investigated. The zero-field critical temperature decreases with increasing the residual resistivity. This result can be explained in terms of the three-dimensional Anderson localization with the mobility edge below the Fermi level The coherence length as a function of x can be explained by the theory of the anisotropic three-dimensional dirty superconductor. However it shows anomalous behavior when x = 0.6. This may be relevant to the change of the crystal structure or the disappearance of the CDW. The effective mass ratio does not depend on x when x <_0.4.

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