Relationship between ionoluminescence emission and bond distance (M-O) in carbonates

Abstract

Ionoluminescence emission spectra induced by 2 MeV protons are reported for a range of carbonates. A major feature in these spectra, are the Mn2+ luminescence centres that appear within all the samples. The emission wavelengths for the Mn2+ are linearly correlated to the metal-oxygen bonding length, both in rhombohedral and orthorhombic lattices for the minerals studied. The Mn2+ band, is in each case related to the corresponding energy level diagram of the mineral's crystal lattice, as this ion perturbs the crystal field term, which for emission in rhombohedral calcite has a value of 1000 cm(-1), and for orthorhombic sites in aragonite is 1200 cm. (c) 2006 Elsevier B.V. All rights reserved.