Configurational entropy can impact crystallization processes, tipping the scales between structures of nearly equal internal energy. Using alloyed single crystals of Gd2PdSi3 in the AlB2-type structure, we explore the formation of complex layer sequences made from alternating, two-dimensional triangular and honeycomb slabs. A four-period and an eight-period stacking sequence are found to be very close in internal energy, the latter being favored by entropy associated with covering the full configuration space of interlayer bonds. Possible consequences of polytype formation on magnetism in Gd2PdSi3 are discussed.
@article{arxiv.2503.18655,
title = {Entropy-assisted, long-period stacking of honeycomb layers in an AlB2-type silicide},
author = {Leonie Spitz and Takuya Nomoto and Shunsuke Kitou and Hironori Nakao and Akiko Kikkawa and Sonia Francoual and Yasujiro Taguchi and Ryotaro Arita and Yoshinori Tokura and Taka-hisa Arima and Max Hirschberger},
journal= {arXiv preprint arXiv:2503.18655},
year = {2025}
}