The Role of Stereoactive Lone Pairs in Templated Vanadium Tellurite Charge Density Matching

The role of charge density matching was investigated in the formation of templated vanadium tellurites under mild hydrothermal conditions. Reactions were conducted using a fixed NaVTeO₅:amine ratio in an ethanol/water solution to isolate the effects of amine structure. The use of 1,4-diaminobutane, 1,3-diaminopropane, and piperazine resulted in three distinct vanadium tellurite connectivities, [V₂Te₂O₁₀]_n²ⁿ⁻ chains, [V₂TeO₈]_n²ⁿ⁻ layers, and [V₂Te₂O₁₀]_n²ⁿ⁻ layers, respectively. Charge density matching with the protonated amines is the primary influence over the structure of each vanadium tellurite anion, as quantified by molecular surface area and geometric decomposition methods. Electron localization functions were calculated using the Stuttgart tight-binding linear muffin-tin orbital, atomic sphere approximation code, to visualize the location and relative size, shape, and orientation of the stereoactive lone pair in the tellurite groups. [C₄H₁₄N₂][V₂Te₂O₁₀]: a = 5.649(5) Å, b = 6.348(5) Å, c = 9.661(5) Å, α = 84.860(5)°, β = 85.380(5)°, γ = 81.285(5)°, triclinic, P1̅ (No. 2), Z = 1.