Magnetic susceptibility, specific heat, and crystal-field effects in neodymium cuprate superconductors

Alternative crystal field parameters for rare-earth ions obtained from various techniques: IV. Comparative analysis of crystal field parameters obtained from inelastic neutron scattering and related studies of RE ions (RE=Er3+, Ho3+, Nd3+, Pr3+) in REBa2Cu3O7−δ high-Tc superconductors

“…No source reference was provided for the definition of V q k by Ravindran et al [37], Uma et al [38] (this paper deals with Pr 3+ ions and other aspects are discussed in Section 3.4), and Senthilkumaran et al [39]. The operators V q k resemble the Wybourne operators, however, judging by the description in text in [37][38][39], the symbols V q k represent another specific tensor notation.…”

“…The operators V q k resemble the Wybourne operators, however, judging by the description in text in [37][38][39], the symbols V q k represent another specific tensor notation. The conversion relations between the actual Wybourne's CFPs B kq in Eq.…”

“…The conversion relations between the actual Wybourne's CFPs B kq in Eq. (2) and the CFPs B q k [37][38][39] may be only indirectly deduced from the CFP values of other authors [28] and [29] cited in [37] and [39], respectively. We obtain: B kq ¼ p k B q k ; p 2 % À0:73; p 4 % 0:89; p 6 % À0:78.…”

“…The original CFPs B q k [37][38][39] converted in this way are also listed in Table 1. Using the standard set of [28] as starting CFPs for fittings of magnetic susceptibility data for Nd 3+ ions NdBa 2 Cu 3Àz Zn z O 7Àd , it was found [37] that although these CFP could reproduce the INS data [28] well, there were appreciable discrepancies between the calculated and experimental magnetic susceptibility data. Subsequently, a stepwise fitting procedure based on varying selected major CFPs was employed) for Nd 3+ ions NdBa 2 Cu 3Àz Zn z O 7Àd , which resulted in one nonstandard set (z = 0) and one standard set (z = 0.02).…”

“…Sarkar and co-workers [37,19] used the ''the n-particle unit irreducible spherical tensor operators'' V q k in their H CF :…”