352 citations · 3.4k across the 93 of their papers we have counts for
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Approximating parabolas as natural bounds of Heisenberg spectra: Reply on the comment of O. Waldmann
H. -J. Schmidt, J. Schnack, Marshall Luban
O. Waldmann has shown that some spin systems, which fulfill the condition of a weakly homogeneous coupling matrix, have a spectrum whose minimal or maximal energies are rather poor…
Quantum rotational band model for the Heisenberg molecular magnet Mo72Fe30
J. Schnack, M. Luban, R. Modler
We derive the low temperature properties of the molecular magnet Mo72Fe30, where 30 Fe(3+) paramagnetic ions occupy the sites of an icosidodecahedron and interact via isotropic nea…
Independent magnon states on magnetic polytopes
J. Schnack, H. -J. Schmidt, J. Richter +1
For many spin systems with constant isotropic antiferromagnetic next-neighbour Heisenberg coupling the minimal energies E_{min}(S) form a rotational band, i.e. depend approximately…
Macroscopic magnetization jumps due to independent magnons in frustrated quantum spin lattices
J. Schulenburg, A. Honecker, J. Schnack +2
For a class of frustrated spin lattices including the kagome lattice we construct exact eigenstates consisting of several independent, localized one-magnon states and argue that th…
Heisenberg exchange parameters of molecular magnets from the high-temperature susceptibility expansion
H. -J. Schmidt, J. Schnack, Marshall Luban
We provide exact analytical expressions for the magnetic susceptibility function in the high temperature expansion for finite Heisenberg spin systems with an arbitrary coupling mat…
Partition functions and symmetric polynomials
H. -J. Schmidt, J. Schnack
We find a close correspondence between certain partition functions of ideal quantum gases and certain symmetric polynomials. Due to this correspondence it can be shown that a numbe…