TY - JOUR
T1 - Magnetic exchange between orbitally degenerate metal ions
T2 - The problem of magnetic anisotropy
AU - Borraós-Almenar, J. J.
AU - Coronado, E.
AU - Clemente-Juan, J. M.
AU - Palii, A. V.
AU - Tsukerblat, B. S.
N1 - Funding Information:
Financial support of the European Union (Network on Molecules as Nanomagnets, HPRN}CT}1999}00012), the Ministerio de Ciencia y Tec-nologmH a (Grant MAT98}0880) and the Generalitat Valenciana (Grant GVDOC00}01}02) are acknowledged. B.S.T. thanks the Universidad de Valencia and the European Science Foundation for a Visiting Professor grant (Programme of Molecular Magnets). J.M.C.J. thanks also the MEC for a post-doctoral fellowship.
PY - 2001/1/1
Y1 - 2001/1/1
N2 - In this paper we show that a strong magnetic anisotropy appears in exchange mixed-valence clusters containing orbitally degenerate metal ions. Combining an effective Hamiltonian approach with the technique of the irreducible tensor operators (ITO) and pseudoangular momentum representation we have solved the problem of magnetic exchange in localized and delocalized (mixed-valence) systems with different overall symmetries (D2h, D3h, D4h). The energy pattern as well as the character of the magnetic anisotropy is closely related to the ground term of the ions, electron transfer pathways, and overall symmetry of the system being affected also by the local crystal fields, spin-orbital interactions, and vibronic interactions. Special attention is paid to the origin of the magnetic anisotropy in the face-shared (D3h) binuclear unit [Ti2Cl9]-3. For this case a very good agreement between calculated and measured χ (T) is obtained.
AB - In this paper we show that a strong magnetic anisotropy appears in exchange mixed-valence clusters containing orbitally degenerate metal ions. Combining an effective Hamiltonian approach with the technique of the irreducible tensor operators (ITO) and pseudoangular momentum representation we have solved the problem of magnetic exchange in localized and delocalized (mixed-valence) systems with different overall symmetries (D2h, D3h, D4h). The energy pattern as well as the character of the magnetic anisotropy is closely related to the ground term of the ions, electron transfer pathways, and overall symmetry of the system being affected also by the local crystal fields, spin-orbital interactions, and vibronic interactions. Special attention is paid to the origin of the magnetic anisotropy in the face-shared (D3h) binuclear unit [Ti2Cl9]-3. For this case a very good agreement between calculated and measured χ (T) is obtained.
KW - Magnetic anisotropy
KW - Magnetic exchange
KW - Mixed-valency
KW - Orbital degeneracy
KW - Vibronic interaction
UR - http://www.scopus.com/inward/record.url?scp=0034814982&partnerID=8YFLogxK
U2 - 10.1006/jssc.2001.9156
DO - 10.1006/jssc.2001.9156
M3 - Article
AN - SCOPUS:0034814982
SN - 0022-4596
VL - 159
SP - 268
EP - 280
JO - Journal of Solid State Chemistry
JF - Journal of Solid State Chemistry
IS - 2
M1 - 99156
ER -