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    The interplay between spin densities and magnetic superexchange interactions: Case studies of monoand trinuclear bis(oxamato)-type complexes
    (Frankfurt am Main : Beilstein-Institut zur Förderung der Chemischen Wissenschaften, 2017) Aliabadi, A.; Büchner, B.; Kataev, V.; Rüffer, T.
    For future molecular spintronic applications the possibility to modify and tailor the magnetic properties of transition-metal complexes is very promising. One of such possibilities is given by the countless derivatization offered by carbon chemistry. They allow for altering chemical structures and, in doing so, to tune magnetic properties of molecular spin-carrying compounds. With emphasis on the interplay of the spin density distribution of mononuclear and magnetic superexchange couplings of trinuclear bis(oxamato)- type complexes we review on efforts on such magneto-structural correlations.
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    Fermi surface nesting in several transition metal dichalcogenides
    (Milton Park : Taylor & Francis, 2008) Inosov, D.S.; Zabolotnyy, V.B.; Evtushinsky, D.V.; Kordyuk, A.A.; Büchner, B.; Follath, R.; Berger, H.; Borisenko, S.V.
    By means of high-resolution angle-resolved photoelectron spectroscopy (ARPES), we have studied the fermiology of 2H transition metal dichalcogenide polytypes TaSe2, NbSe2 and Cu0.2NbS 2. The tight-binding model of the electronic structure, extracted from ARPES spectra for all three compounds, was used to calculate the Lindhard function (bare spin susceptibility), which reflects the propensity to charge density wave (CDW) instabilities observed in TaSe2 and NbSe 2. We show that though the Fermi surfaces of all three compounds possess an incommensurate nesting vector in the close vicinity of the CDW wave vector, the nesting and ordering wave vectors do not exactly coincide, and there is no direct relationship between the magnitude of the susceptibility at the nesting vector and the CDW transition temperature. The nesting vector persists across the incommensurate CDW transition in TaSe2 as a function of temperature despite the observable variations of the Fermi surface geometry in this temperature range. In Cu0.2NbS2, the nesting vector is present despite different doping levels, which leads us to expect a possible enhancement of the CDW instability with Cu intercalation in the Cu xNbS2 family of materials.