Synthesis, structure, and properties of Li2Pb2CuB4O10 with isolated [CuB4O10]6− units

The copper borate Li2Pb2CuB4O10 has been synthesized in air by the standard solid-state reaction at temperature in the range 550–650 °C and the structure of Li2Pb2CuB4O10 was determined by single-crystal X-ray diffraction. Li2Pb2CuB4O10 crystallizes in the monoclinic space group C2/c (no. 15) with a = 16.8419(12), b = 4.7895(4), c = 13.8976(10) Å, and β = 125.3620(10)°, V = 914.22(12) Å3, and Z = 4, as determined by single-crystal X-ray diffraction. The Li2Pb2CuB4O10 structure exhibits isolated units of stoichiometry [CuB4O10]6− that are built from CuO4 distorted square planes and triangular BO3 groups. The IR spectroscopy and thermal analysis investigations of Li2Pb2CuB4O10 are also presented.

Research highlightsLi2Pb2CuB4O10 is the first of a new family of lithium lead copper borates in the system Li2O–PbO–CuO–B2O3. It exhibits isolated units of stoichiometry [CuB4O10]6− that are built from CuO4 distorted square planes and triangular BO3 groups. The compound melts congruently and therefore large, high-quality single crystals can be grown easily.