Journal of Physical Studies 9(3), 243–247 (2005) DOI: https://doi.org/10.30970/jps.09.243 THE PECULARITIES IN METAL-INSULATOR TRANSITION DUE TO COMPOSITION CHANGE IN SEMICONDUCTING Zr1-хScхNiSn SOLID SOLUTION. I. ACCEPTOR IMPURITIES O. I. Bodak{1}, V. A. Romaka{2,3},{ }Yu. V. Stadnyk{1}, M. G. Shelyapina{4}, D. Fruchart{5}, L. P.  Romaka{1}, V. F. Chekurin{3}, Yu. K. Gorelenko{1} {1} Ivan Franko National University of Lviv, 6 Kyryla i Mefodija St., Lviv, UA-79005, Ukraine, e-mail: stadnyk_yuriy@franko.lviv.ua; {2}National University ‟Lvivska Politechnika”, 12 Bandera St., Lviv, UA-79013, Ukraine, e-mail: vromaka@polynet.lviv.ua; {3}Ya. Pidstryhach Institute for Applied Problems of Mechanics and Mathematics, National Academy of Sciences of Ukraine, 3-b Naukova St., Lviv, UA-79053, Ukraine; {4}V. A. Fock Institute of Physics, St.-Petersburg State University, 1 Ulyanovskaya St., Petrodvorets, St.-Petersburg, 198504, Russia; {5}Laboratoire de Cristallographie, CNRS, BP 166, 38042 Grenoble Cedex 9, France.

The role of the impurity acceptor band on the conductivity of the heavy dopped and compensated {\em M}NiSn ({\em M} = Ti, Zr, Hf) intermetallic semiconductors was determined. A scheme of the impurity band transformation in the $n$-ZrNiSn compound dopped with the acceptor impurities was proposed. A simulation of the electronic structure for the Zr$_{1 - x}$Sc$_{x}$NiSn solid solution was performed. Magnetic susceptibility oscillations around the transition of conductivity metal-insulator during the change in Zr$_{1 - x}$Sc$_{x}$NiSn solid solution composition were first experimentally observed. This transition we account for the Anderson transition. These observed oscillations indicate the existence of the Coulomb gap in impurity band of semiconductor during the change of doping level and compensation.

PACS number(s): 71.20.Nr; 72.20.Pa; 72.80.Ga; 75.20.Ck; 81.05.Hd

pdf