TmSe, magnetic properties

Magnetic properties of semiconducting TmSe, jTe, (after Boppart 1983)... 

Within the fee RSe series TmSe exhibits quite unique properties, since it shows intermediate-valence behavior (Bucher et al. 1975, Campagna et al. 1974, Launois et al. 1980) in combination with low-temperature magnetic order... 

TmSe is another interesting example for anomalous elastic properties. TmSe with the two magnetic configurations 4f (Tm ) and 4f (Tm ) exhibits an antiferromagnetic ordering at Tjf 3K. As seen from table 6, is small and V < 0. Very illustrative is the semiconductor-metal transition in the TmSe-TmTe system (Boppart 1985). In fig. 57 the phase diagram p-V-x exhibits close similarities to the common liquid-gas transition (TmSei Te ). The critical point is givey by — 0.45, — 0.8 GPa. Because of the same symmetry between the... 

I. Electronic and lattice properties. In this section the electronic properties of magnetically ordering divalent EuSe arc altered by introducing TmSe, provoking possible intermediate valence. In this pseudobinaiy alloy system the substitution of Eu by Tm decreases the lattice constant, but since divalent Tm has a smaller ionic radius than divalent Eu there is no lattice pressure exerted on Tm as long as the compounds are semiconductors (see fig. 106). Thus Tm as well as Eu remain divalent. Kaldis et al. (1982) have shown that in the pseudobinary alloy system a number of miscibility gaps exist, but at x = 0.2 a compositionally induced SMT is found, i.e., for x <0.2 the compounds... 

NpTe no magnetic scattering was observed at low temperatures. More recently (Burlet, unpublished), long-range order has been observed with neutron diffraction, and the magnetic moment is It seems likely that the properties of NpTe may be sensitive to the stoichiometry, much in the same way as they are for TmSe. The ordering observed in the new sample has the type II form with A = (, j, j) and Tf, = 40.5 K. 

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