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arXiv · 0812.4126

Numerically exact and approximate determination of energy eigenvalues for antiferromagnetic molecules using irreducible tensor operators and general point-group symmetries

R. Schnalle·J. Schnack
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Abstract

Numerical exact diagonalization is the ultimate method of choice in order to discuss static, dynamic, and thermodynamic properties of quantum systems. In this article we consider Heisenberg spin-systems and extend the range of applicability of the exact diagonalization method by showing how the irreducible tensor operator technique can be combined with an unrestricted use of general point-group symmetries. We also present ideas how to use spin-rotational and point-group symmetries in order to obtain approximate spectra.

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R. Schnalle, J. Schnack. 2008-12-22. Numerically exact and approximate determination of energy eigenvalues for antiferromagnetic molecules using irreducible tensor operators and general point-group symmetries. https://doi.org/10.1103/physrevb.79.104419

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