New structure type of ternary intermetallic borides CePt2B

The crystal structure of a new ternary boride CePt2B, space group P6(2)22 ( N180), a = 5.4898(5) Angstrom, c = 7.8860(9) Angstrom, Z = 3, V = 205.83(1) Angstrom, rho = 13.097 g cm(-3), mu = 117.63 mm(-1) was refined to R = 0.0 384, wR2 = 0.0926 from single-crystal X-ray diffraction data. Rietveld refi nement of the X-ray powder data collected from the CePt2B sample annealed a t 1070 K confirmed the structural model obtained by single-crystal refineme nt (a = 5.4811(3) Angstrom, c = 7.8830(2) Angstrom, R-F = 0.0497, R-B = 0.0 668 from X-ray powder diffraction). This is the first representative of a n ew structure type of intermetallic compound. Preliminary magnetic measureme nts show the sample to be nonsuperconducting at 2 K with possible magnetic ordering below 7 K. (C) 2000 Elsevier Science S.A. All rights reserved.