Synthesis, Structure, and Properties of the Noncentrosymmetric Pyroborate BaCuB2O5

✍ Scribed by Robert W Smith; Douglas A Keszler

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 384 KB
• Volume: 129
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1996.7204

✦ Synopsis

The new noncentrosymmetric pyroborate BaCuB 2 O 5 has been synthesized and its structure determined by single-crystal X-ray methods. It crystallizes in the monoclinic space group C2 with a cell of dimensions a‫,)1(584.6؍‬ b‫,)1(561.9؍‬ c‫)1(179.3؍‬ A s , and ‫.°)1(41.69؍‬ The structure was determined from 1281 unique reflections and refined to the final residuals R‫930.0؍‬ and wR‫.940.0؍‬ It is composed of highly distorted [CuO 4 ] squares and double-triangular [B 2 O 5 ] groups that are connected to form infinite two-dimensional layers. The layers are stacked parallel to (001), and the Ba atoms interleave successive layers. Parallel alignment of the pyroborate groups is conductive to high efficiency for optical frequency conversion. The magnetic moment at 22°C is 1.69$0.03 B .