53 citations · 58 across the 5 of their papers we have counts for
5 papers
Van Der Waals Revisited
K. Baerwinkel, J. Schnack
The van-der-Waals version of the second virial coefficient is not far from being exact if the model parameters are appropriately chosen. It is shown how the van-der-Waals resemblan…
Quantum numbers for relative ground states of antiferromagnetic Heisenberg spin rings
K. Baerwinkel, P. Hage, H. -J. Schmidt +1
We suggest a general rule for the shift quantum numbers k of the relative ground states of antiferromagnetic Heisenberg spin rings. This rule generalizes well-known results of Mars…
Improved upper and lower energy bounds for antiferromagnetic Heisenberg spin systems
K. Baerwinkel, H. -J. Schmidt, J. Schnack
Large spin systems as given by magnetic macromolecules or two-dimensional spin arrays rule out an exact diagonalization of the Hamiltonian. Nevertheless, it is possible to derive u…
On cyclically shifted strings
K. Baerwinkel, H. -J. Schmidt, J. Schnack
If a string is cyclically shifted it will re-appear after a certain number of shifts, which will be called its order. We solve the problem of how many strings exist with a given or…
Quasi-Particle Picture for Monatomic Gases
K. Baerwinkel, J. Schnack, U. Thelker
A quasi-particle theory for monatomic gases in equilibrium is formulated and evaluated to yield the exact virial contributions to the thermodynamic state functions in lowest order…