High-pressure synthesis and crystal structure of non-centrosymmetric K2Ca3(CO3)4. Issue 38 (14th September 2021)

• Record Type: Journal Article
• Authors: Rashchenko, Sergey V.; Shatskiy, Anton F.; Ignatov, Mark A.; Arefiev, Anton V.; Litasov, Konstantin D.
• Is Part Of: CrystEngComm. Volume 23:Issue 38(2021)
• Page Start: 6675
• Page End: 6681
• Publication Date: 2021-09-14
• Subjects: Crystals -- Periodicals; Crystal growth -- Periodicals; Crystallography -- Periodicals; Cristaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Cristallographie -- Périodiques; 548
• DOI: 10.1039/d1ce00882j
• Languages: English
• ISSNs: 1466-8033

Abstract

Abstract : A new non-centrosymmetric K2 Ca3 (CO3 )4 crystal ( P 21 21 21, a = 7.39134(18) Å, b = 8.8153(2) Å, c = 16.4803(4) Å) was synthesized in a multi-anvil press at a pressure of 3 GPa and temperature of 975 °C. Abstract : A new non-centrosymmetric K2 Ca3 (CO3 )4 crystal ( P 21 21 21, a = 7.3905(2) Å, b = 8.8156(3) Å, c = 16.4817(5) Å) was synthesized in a multi-anvil press at a pressure of 3 GPa and temperature of 975 °C. The compound is homeotypic to A3 B2 (BO3 )4 (A = Ca, Sr, Ba; B = REE, Y, Bi) orthoborates with the Pnma symmetry, but is characterized by the non-centrosymmetric arrangement of (CO3 ) anions within the Pnma -pseudosymmetric cation sublattice. K2 Ca3 (CO3 )4 represents a pure carbonate member of the extended M5 (XO3 )4 (X = B, C, B/C) structural type, which also includes A3 B2 (BO3 )4 orthoborates as well as recently synthesized mixed orthoborate–carbonates of Ba and Sr. Crystallochemical considerations suggest that cation-substituted (REE, Cs, Sr, and Ba) derivatives of K2 Ca3 (CO3 )4 can probably be synthesized at significantly lower pressures than 3 GPa, which is required to stabilize the compound itself.