A fresnoite-structure-related mixed valent titanium(III/IV) chlorosilicate, Ba3Ti2Si4O14Cl: A flux crystal growth route to Ti(III) containing oxides

作者：Abeysinghe Dileka; Smith Mark D; zur Loye Hans Conrad

来源：Journal of Solid State Chemistry, 2017, 250: 128-133.

DOI：10.1016/j.jssc.2017.03.026

• Mixed valent titanium silicate
• Flux crystal growth
• Mg reducing agent
• Magnetic susceptibility

Single crystals of mixed valent barium titanium(III/IV) chlorosilicate, Ba3Ti2Si4O14Cl0.91O0.09, were grown in a high temperature molten chloride flux involving an in situ reduction step. The fresnoite structure related Ba3Ti2Si4O14Cl0.91O0.09 crystallizes in the tetragonal space group P4/mbm with lattice parameters of a=8.6717(2) angstrom, c=18.6492(5) angstrom. The title compound exhibits a 3D structure consisting of 2D layers of fused 11209 and Si4O12 groups and 2D layers of fused Ti2O9Cl2 and Si2O7 groups that are linked via barium atoms. The in situ reduction of Ti(IV) to Ti(III) is achieved via the addition of metallic Mg to the flux to function as the reducing agent. The temperature dependence of the magnetic susceptibility shows simple paramagnetism above 100 K. There is a discontinuity in the susceptibility data below 100 K, which might be due to a structural change that takes place resulting in charge ordering.

• 出版日期2017-6