Simple model for complex structures

The complex structures of the low-temperature phases of light actinides are analyzed in terms of a simple model involving Pettifor{close_quote}s structural energy difference theorem in combination with an estimate of the structural dependence of the electrostatic interaction in the solid. With this simple model the complex structures of the actinides are contrasted to the simpler ones of the transition metals, and in agreement with observations we find that at ambient conditions the f-electron elements favor distorted structures, whereas d-electron metals {open_quotes}prefer{close_quotes} cubic or hcp structures. {copyright} {ital 1998} {ital The American Physical Society}