Structural phase transition in Zn_1.98Mn_0.02P₂O₇: EPR evidence for enhanced line broadening and large zero-field splitting parameter in high temperature phase

Abstract

Abstract

Origin of Blue-Green Emission in α-Zn2P2O7 and Local Structure of Ln3+ Ion in α-Zn2P2O7:Ln3+ (Ln = Sm, Eu): Time-Resolved Photoluminescence, EXAFS, and DFT Measurements

“…Figure b depicts the unit cell of α-Zn 2 P 2 O 7 . A detailed description of the crystal structure and the other high-temperature phase of α-Zn 2 P 2 O 7 was reported in our earlier work. , …”

“…A detailed description of the crystal structure and the other high-temperature phase of α-Zn 2 P 2 O 7 was reported in our earlier work. 22,23 At low temperature Zn 2 P 2 O 7 crystallizes in a 6-fold superstructure (α polymorph) with I2/c space group. The PAW-GGA calculated equilibrium lattice parameters, mono-clinic angles, and bond lengths are summarized in Table S1 in the Supporting Information along with experimentally determined values (by Rietveld refinements).…”

“…Recently zinc pyrophosphate has gained significant attention as a luminescence host, and a great deal of work has been done in the last 5 years or so. ,, In fact, our group is also extensively involved in spectroscopic measurements on lanthanide and transition metal ion doped α-Zn 2 P 2 O 7 for probing structural phase transitions, oxidation state of the dopant ion such as Mn, local structure, photoluminescence properties, and use as phosphor materials. − In the case of europium- and samarium-doped samples, , it has been observed that Eu 3+ /Sm 3+ was distributed at both five- and six-coordinated Zn 2+ sites; while complete host to dopant energy transfer takes place in the case of Eu 3+ , it is absent for Sm 3+ . Such statements have been made solely on the basis of photoluminescence (PL) emission and lifetime spectroscopy in our earlier works.…”