SrC2O5 is an Inorganic Pyrocarbonate Salt with C2O5(2-) Complex Anions

摘要

The synthesis of a novel type of carbonate, namely of the inorganic pyrocarbonate salt Sr[C2O5], which contains isolated [C2O5](2-)-groups, significantly extends the crystal chemistry of inorganic carbonates beyond the established sp(2)- and sp(3)- carbonates. We synthesized Sr[C2O5] in a laser-heated diamond anvil cell by reacting Sr[CO3] with CO2. By single crystal synchrotron diffraction, Raman spectroscopy, and density functional theory (DFT) calculations, we show that it is a pyrocarbonate salt. Sr[C2O5] is the first member of a novel family of inorganic carbonates. We predict, based on DFT calculations, that further inorganic pyrocarbonates can be obtained and that these will be relevant to geoscience and may provide a better understanding of reactions converting CO2 into useful inorganic compounds.