The antiferromagnetism of CrSb (From a book)
CrSb
CrSb, which takes the NiAs-type structure, is an antiferromagnet with TN = 718K and a simple spin arrangement shown in Fig. 3.45.
Magnetic moment of a Cr atom is equal or close to Cr 3+ moment (3.0μB) with g = 2. As shown in Fig. 3.38,the a-axis of CrSb is much longer than that of CrAs, while difference of the c-axis between CrSb and CrAs is small (5.65 ˚ A for CrS band 5.45 ˚ A for CrAs). Such a large a-axis of CrSb brings about narrow width of the 3d band and enhancement of intra-atomic exchange interaction, consequently the large moment. As we mentioned in Sect. 3.4.2, temperature dependence of susceptibility of CrSb behaves like an antiferromagnet with two sublattice [71]. This behavior is quite different from that in the temperature region TN ≤ T ≤ Tt for CrAs. We can obtain θP = −200K and Cr-moment 2.9μB for CrSb from the Curie–Weiss type susceptibility together with assumption of g = 2. The value of 2.9μB thus obtained is in good agreement with 3.0 and 2.7μB by the neutron diffraction measurements showninFig. 3.45. As compared with CrAs, CrSb seems to have a strong localized character. This kind of tendency is also seen in Mn-pnictides such as MnBi, MnSb, MnAs, and MnP (see Fig. 3.11). The relation between a-axis and magnetic moment shown in Figs. 3.38 and 3.11 seems to suggest a way of approach to understand the magnetism of 3d-pnictides. There is relevant discussion in Sect. 4.2 of Part II.
Resistivity of CrSb above TN shows temperature dependence like a semiconductor [72]; however, it is unsure whether such behavior of resistivity arises from an intrinsic property of CrSb or slight crystal decomposition at high temperatures such as Sb-precipitation as seen in MnSb (Sect. 1.4 and Fig. 1.6).
Reference: From the book " Electronic Structure and Magnetism of 3d-Transition Metal Pnictides "
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