352 citations · 781 across the 16 of their papers we have counts for
6 papers · 1 filter
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…
Bounding and approximating parabolas for the spectrum of Heisenberg spin systems
H. -J. Schmidt, J. Schnack, Marshall Luban
We prove that for a wide class of quantum spin systems with isotropic Heisenberg coupling the energy eigenvalues which belong to a total spin quantum number S have upper and lower…
Transition from quantum to classical Heisenberg trimers: Thermodynamics and time correlation functions
D. Mentrup, H. -J. Schmidt, J. Schnack +1
We focus on the transition from quantum to classical behavior in thermodynamic functions and time correlation functions of a system consisting of three identical quantum spins s th…
Ground state properties of antiferromagnetic Heisenberg spin rings
K. Baerwinkel, H. -J. Schmidt, J. Schnack
Exact ground state properties of antiferromagnetic Heisenberg spin rings with isotropic next neighbour interaction are presented for various numbers of spin sites and spin quantum…
Thermodynamic fermion-boson symmetry in harmonic oscillator potentials
H. -J. Schmidt, J. Schnack
A remarkable thermodynamic fermion-boson symmetry is found for the canonical ensemble of ideal quantum gases in harmonic oscillator potentials of odd dimensions. The bosonic partit…