Structural investigation of the A-site vacancy in scheelites and the luminescence behavior of two continuous solid solutions A1–1.5xEux□0.5xWO4 and A0.64–0.5yEu0.24Liy□0.12–0.5yWO4 (A = Ca, Sr; □ = vacancy)

Abstract

A detailed structural characterization on A_1–1.5xEu_x□_0.5xWO₄ and A_0.64–0.5yEu_0.24Li_y□_0.12–0.5yWO₄ (A = Ca, Sr; □ = vacancy) prove the A-site vacancy mechanism for charge balance.