Neutron-Diffraction Study of Lithium Sulfate Monohydrate

Abstract

A neutron‐diffraction study of Li₂SO₄·H₂O has shown the water molecule to be weakly hydrogen bonded to the oxygen atom (O₅) of an equivalent water molecule (O₅–O₅′ = 2.95 ± 0.01 Å) and to an oxygen atom (O₁) of a sulfate ion (O₅–O₁ = 2.87 ± 0.02 Å). The O₅–H₂···O₅′ and O₅–H₁···O₁ angles are 151.0 ± 1.0° and 152.6 ± 3.4°. The dimensions of the water molecule (after correction for thermal motion) are: O₅–H₁ = 0.99 ± 0.03 Å, O₅–H₂ = 1.00 ± 0.55 Å, H₁–H₂ = 1.64 ± 0.05 Å, and H₁–O₅–H₂ = 110.6 ± 2.4°. The $R$ factor (for F²) based on the $\text{hk0}$ , $\text{h0l}$ , and $\text{0kl}$ reflections is 6.1%.