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\begin{document}
\title{Crystal structures of ternary gadolinium silicides}
\author{V. Mykhalichko}
\affiliation{Department of Inorganic Chemistry, Ivan Franko National University of Lviv,   Kyryla i Mefodiya St. 6, UA-79005 Lviv, Ukraine  }
\author{R. Kozak}
\affiliation{Laboratory of Crystallography, Department of Materials, ETH Zurich,  Vladimir-Prelog-Weg 5, CH-8093 Zurich, Switzerland  }
\author{P. Demchenko}
\affiliation{Department of Inorganic Chemistry, Ivan Franko National University of Lviv,   Kyryla i Mefodiya St. 6, UA-79005 Lviv, Ukraine  }
\author{R. Gladyshevskii}
\affiliation{Department of Inorganic Chemistry, Ivan Franko National University of Lviv,   Kyryla i Mefodiya St. 6, UA-79005 Lviv, Ukraine  }
\begin{abstract}
\hspace{15pt}The crystal structure of Gd$_{2}$Re$_{3}$Si$_{5}$ was solved by
direct methods in space group \textit{P}4/\textit{mnc}, using the SHELX-97 program package. The crystal structure of Gd$_{2}$Pt$_{3}$Si$_{5}$ was refined by the Rietveld method, using the CSD program package. The crystal structure of the ternary compound Gd$_{2}$Re$_{3}$Si$_{5}$ belongs to the structure type U$_{2}$Mn$_{3}$Si$_{5}$ (\textit{tP}40, \textit{P}4/\textit{mnc},\textit{ a} = 10.95564(13), \textit{c} = 5.56326(11) \AA{}, atom coordinates: Gd 8\textit{h} 0.26249(5) 0.42271(5) 0; Re1 8\textit{h }0.14676(4) 0.12315(4) 0; Re2 4\textit{d }0 1/2 1/4; Si1 8\textit{h }0.0267(3) 0.3149(3) 0; Si2 8\textit{g }0.17183(18) 0.67183(18) 1/4; Si3 4\textit{e }0 0 0.2567(9)), whereas the crystal structure of Gd$_{2}$Pt$_{3}$Si$_{5}$ adopts the U$_{2}$Co$_{3}$Si$_{5}$ type (\textit{oI}40, \textit{Ibam}, \textit{a} = 9.9224(2), \textit{b} = 11.3997(2), \textit{c} = 5.99300(9) \AA{}, atom coordinates: Gd 8\textit{j }0.2671(2) 0.3717(3) 0; Pt1 8\textit{j }0.1122(2) 0.1374(2) 0; Pt2 4\textit{b }1/2 0 1/4; Si1 8\textit{j} 0.356(1) 0.116(1) 0; Si2 8\textit{g }0 0.2710(9) 1/4; Si3 4\textit{a }0 0 1/4). The structures of Gd$_{2}$Re$_{3}$Si$_{5}$ and Gd$_{2}$Pt$_{3}$Si$_{5}$ can be described as arrangements of one-dimensional structural columns parallel to the crystallographic direction [001], also found in the structure type CaBe$_{2}$Ge$_{2}$.

\end{abstract}
\maketitle

\end{document}
