Structural Behavior of Minrecordite Carbonate Mineral upon Compression: Effect of Mg → Zn Chemical Substitution in Dolomite-Type Compounds.

ABSTRACT: We report the structural behavior and compressibility of minrecordite, a naturally occurring Zn-rich dolomite mineral, determined using diamond-anvil cell synchrotron X-ray diffraction. Our data show that this rhombohedral CaZn_0.52Mg_0.48(CO₃)₂ carbonate exhibits a highly anisotropic behavior, the c axis being 3.3 times more compressible than the a axis. The axial compressibilities and the equation of state are governed by the compression of the [CaO₆] and [ZnO₆] octahedra, which are the cations in larger proportion in each layer. We observe the existence of a dense polymorph above 13.4(3) GPa using Ne as a pressure-transmitting medium, but the onset pressure of the phase transition decreases with the appearance

SUBMITTER: Santamaria-Perez D 

PROVIDER: S-EPMC10034829 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature