Luminescence and Dosimetric Performances of KMgF3 Crystals Doped with Metal Impurity Ions

Abstract

Thermoluminescence spectra have been recorded for crystals of pure KMgF3, KMgF3:Pb2+ and KMgF3:Eu3+, with the aim of identifying new phosphors for radiation dosimetry. Glow peaks, due to thermal activation of colour centres formed by ß or ? irradiation, were measured in both pure and doped materials. Typical thermoluminescence signals due to Pb2+ or Eu3+ impurities have been obtained, besides those of the host KMgF3. The intensity of the thermoluminescence peaks is not very high in Pb2+-doped samples, while Eu3+ ions are found to be excellent activators, as usual for rare earth impurities. In KMgF3:Eu3+ a new prominent peak has been found very efficient for monitoring radiation doses, because of its high sensitivity, good stability over time and elevated activation energy.

Photoluminescence of KZnF3:Tl and KMgF3:Tl crystals

“…Already in the first order on any non-fullysymmetric deformation the triplet states 4u are mixed to the states ( 3 3u , 3 5u ), and transitions leading to the B absorption band become allowed. The triplet states 3 * 4u , 1 * 4u do not admix to the metastable state 3 1u in either the first or second order of the perturbation theory, so the usual electron-vibration mechanism is not effective for allowing the transition 1 1g ↔ 3 1u . However, the magnetic field mixes the states 3 1u and 3 4u .…”

“…These systems are interesting as promising materials for tunable lasers in the UV region. The KMgF 3 :Tl + crystals are also known as good scintillators [3]. 1 Author to whom any correspondence should be addressed.…”

Optical absorption of KZnF3:Tl+and KMgF3:Tl+crystals

“…Crystals of alkali halides doped with mercury-like ions have been traditional objects of experimental and theoretical investigation for several decades; a number of reviews are devoted to optical properties of such crystals [1][2][3]. Fluorine crystals doped with ions having an external ns 2 shell ('s 2 ions') are much less investigated, though these objects are interesting as active materials for tunable solid-state lasers and scintillators [4][5][6]. Among the fluorine compounds the perovskite-like ABF 3 crystals are of special interest.…”

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

“…An added advantage of KMgF 3 in the field of radiation dosimetry is its effective atomic number ( Z eff ) of about 13.4, which is a desirable range for a TL material. 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 .…”