The stability of coordination polyhedrons and distribution of europium ions in Ca6BaP4O17. Issue 38 (29th September 2020)

• Record Type: Journal Article
• Authors: Ma, Fengkai; Zhou, Rongfu; Su, Fang; Ou, Yiyi; Liang, Hongbin
• Is Part Of: Physical chemistry chemical physics. Volume 22:Issue 38(2020)
• Page Start: 22096
• Page End: 22106
• Publication Date: 2020-09-29
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/d0cp03895d
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : Polyhedron-tilt-induced coordination structural transformation and the stabilities are intimately related to dynamic environments. Abstract : In this work, the coordination polyhedron stabilities and distributions of europium ions in Ca6 BaP4 O17 (CBPO) luminescent materials are investigated. The density functional theory (DFT)-based first principles calculation results show that the PO4 tetrahedrons can tilt in the structure, which leads to the atomic distortion of O13 and O12 in CBPO and the Eu 2+ /Eu 3+ -doped systems. The energy scale of about ∼0.1 eV suggests that stabilities of coordination polyhedrons are easily influenced by dynamic factors. The atomic distortion and vacancy of work as charge compensations in CBPO:Eu 3+, and three lattice sites of europium are extracted and summarized. The X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) confirm that Eu 3+ can occupy the Ca1, Ca2 and Ba sites of CBPO. The combination of first principles calculation and X-ray absorption fine structure (XAFS) provides more information about microstructures of luminescent materials.