Radiation effects in pure and RE doped KMgF₃

Probing site-selective doping and charge compensating defects in KMgF3: insights from a hybrid DFT study

“…For example, Haiquan Su et al explained the emission maximum at 420 nm by the energy transfer from Eu 2+ to the color center and the oxygen centers; 26 while in another study, it has been assigned to the f-f transition of Eu 3+ . 50 Similarly, Shiran et al reported narrow optical emission bands of Eu 3+ in the region of 520–630 nm, 47 while Pathak et al indicated broad emissions in the wavelength region of 300–500 nm. The second issue is related to the presence of vacancy defects in the host crystal structure.…”

“…24 This has motivated a large number of experimental studies to investigate and explain the optical properties of Eu-doped KMgF 3 in the last few years. 25–50 However, existing literature shows different opinions related to the origin of the observed optical behaviour of Eu-doped KMgF 3 . The first and most common issue is related to the assignment of a particular optical peak.…”

“…The last but not least issue is related to the oxidation state of Eu in KMgF 3 . A few groups believed the presence of either Eu 2+ 26,30,32,38,42,45 or Eu 3+ , 47–50 while some groups reported that Eu exists as both Eu 2+ and Eu 3+ . 31…”

“…The last but not least issue is related to the oxidation state of Eu in KMgF 3 . A few groups believed the presence of either Eu 2+26,30,32,38,42,45 or Eu 3+ , [47][48][49][50] while some groups reported that Eu exists as both Eu 2+ and Eu 3+ . 31 Therefore, a detailed knowledge of the microscopic structures of different kinds of defects and vacancy clusters is very much essential to unambiguously explain the origin of the optical properties of Eu-doped KMgF 3 .…”