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Single crystals of Na2Cu+[Cu2+3O](AsO4)2Cl (1) and Cu3[Cu3O]2(PO4)4Cl2 (2) were prepared by chemical vapor transport reactions. Both crystal structures are based upon the same [O2Cu6]8+ chains formed by corner-sharing (OCu4)6+ tetrahedra and interconnected by (TO4)3− (T = P, As) tetrahedra into porous {[OCu3](TO4)2Cl}3− frameworks. The channels within the frameworks are occupied by Na+, Cu+ and Cl− ions in the crystal structure of 1, whereas the channels in the structure of 2 contain edge-sharing CuO4Cl tetragonal pyramids. Both compounds are structurally related to the previously described synthetic Na2Cu+[Cu2+3O](PO4)2Cl and NaCu2+[Cu2+3O](PO4)2Cl. The compound 2 is structurally and chemically related to yaroshevskite, Cu3[Cu3O]2(VO4)4Cl2, a mineral discovered in volcanic fumaroles, but the two structure types are drastically different. The crystal chemical analysis of the title and related compounds allows to recognize a family of at least four compounds based upon {[OCu3](TO4)2Cl}3− frameworks with channels occupied by different chemical constituents. [ABSTRACT FROM AUTHOR]

A novel polymorph of RbCuCl3 (rubidium copper trichloride), denoted ϵ‐RbCuCl3, has been prepared by chemical vapour transport (CVT) from a mixture of CuO, CuCl2, SeO2 and RbCl. The new polymorph crystallizes in the orthorhombic space group C2221. The crystal structure is based on an octahedral framework of the 4H perovskite type. The Rb+ and Cl− ions form a four‐layer closest‐packing array with an ABCB sequence. The Cu2+ cations reside in octahedral cavities with a typical [4 + 2]‐Jahn–Teller‐distorted coordination, forming four short and two long Cu—Cl bonds. ϵ‐RbCuCl3 is the most structurally complex and most dense among all currently known RbCuCl3 polymorphs, which allows us to suggest that it is a high‐pressure phase, which is unstable under ambient conditions. [ABSTRACT FROM AUTHOR]

Three novel copper compounds, Rb4Cu4OCl10 (I), Rb[Cu3O](SeO3)2Cl (II), and RbCu3(OH)(SeO3)Cl4(H2O)3 (III) were prepared by chemical vapor transport (CVT) reactions method from mixtures of CuO, SeO2, RbCl, and CuCl2. The crystal structures of the three compounds were determined by direct methods. Compound I is a Rb analogue of ponomarevite, K4Cu4OCl10. Its crystal structure contains {[OCu4]Cl10}4- clusters with oxocentered [OCu4]6+ tetrahedra as cores. The clusters are linked by the Rb+ cations. The crystal structure of II contains complex {[O2Cu6](SeO3)4Cl2}2- layers formed by dimers of edge-sharing [OCu4]6+ tetrahedra interlinked via selenite groups and Cl- anions. The crystal structure of III is based upon {[(OH)Cu3](SeO3)}3+ layers formed by the [(OH)Cu3]5+ tetrahedra attached to (SeO3)2- groups. The layers are linked via Cl- anions and via hydrogen bonds to H2O molecules. [ABSTRACT FROM AUTHOR]

The crystal structure of Cs2CuP2O7 [monoclinic, Cc, a = 7.460(6), b = 12.973(10), c = 9.980(8) Åβ = 111.95(2) ° , V = 895.8(12) Å3] prepared by solid-state reactions is based upon open framework formed by corner sharing between CuO4 distorted squares and P2O7 groups. The framework is porous and has a very low framework density of 13.4 Cu+P atoms per 1 nm3. Cs+ cations reside in large framework cavities. The heteropolyhedral network in the title compound is based upon three-dimensional (3;4)-connected net that has a three-membered CuP2 ring as its elementary unit. In terms of reticular chemistry, this net should be considered as an augmented diamond (dia) net. The Cu-P net can be obtained from the latter by the replacement of its nodes by the CuP2 triangles. This replacement is strongly non-centrosymmetric, since all CuP2 triangles are oriented along the same direction, which provides a crystal chemical explanation for the absence of a symmetry centre in the structure. Cs2CuP2O7 is the first compound in the A2CuP2O7 family (A alkaline metal), which is based upon threedimensional copper pyrophosphate framework. [ABSTRACT FROM AUTHOR]

The crystal structure of paratooite-(La) has been solved using crystals from the type locality, Paratoo copper mine, near Yunta, Olary Province, South Australia, Australia. The mineral is orthorhombic, Pbam, a = 7.2250(3) Å, b = 12.7626(5) Å, c = 10.0559(4) Å, V = 927.25(6) Å3, and R1 = 0.063 for 1299 unique observed reflections. The crystal structure contains eight symmetrically independent cation sites. The La site, which accommodates rare earth elements (REEs), but also contains Sr and Ca, has a tenfold coordination by seven carbonate groups. The Ca, Na1, and Na2 sites are coordinated by eight, eight, and six O atoms, respectively, forming distorted CaO8 and Na1O8 cubes, and Na2O6 octahedra. The Cu site is occupied solely by copper and possess a distorted octahedral coordination with four short (1.941 Å) and two longer (2.676 Å) apical Cu–O bonds. There are three symmetrically independent carbonate groups (CO3)2− with the average bond lengths equal to 1.279, 1.280, and 1.279 Å for the C1, C2, and C3 sites, respectively. The crystal structure of paratooite-(La) can be described as a strongly distorted body-centered lattice formed by metal cations with (CO3)2− groups filling its interstices. According to the chemical and crystal-structure data, the crystal-chemical formula of paratooite-(La) can be described as (La0.74Ca0.11Sr0.07)4CuCa(Na0.75Ca0.15)(Na0.63)(CO3)8 or REE2.96Ca1.59Na1.38CuSr0.28(CO3)8. The idealized formula can be written as (La,Sr,Ca)4CuCa(Na,Ca)2(CO3)8. The structure of paratooite is a 1 × 2 × 2 superstructure of carbocernaite, CaSr(CO3)2. The superstructure arises due to the ordering of the chemically different Cu2+ cations, on one hand, and Na+ and Ca2+ cations, on the other hand. The formation of a superstructure due to the cation ordering in paratooite-(La) compared to carbocernaite results in the multiple increase of structural complexity per unit cell. Therefore, paratooite-(La) versus carbocernaite represents a good example of structural complexity increasing due to the increasing chemical complexity controlled by different electronic properties of mineral-forming chemical elements (transitional versus alkali and alkaline earth metals). [ABSTRACT FROM AUTHOR]

The Se–Cl interactions in five selenite chlorides (α,β-Zn2(SeO3)Cl2 (sofiite and its polymorph), α,β-Cu5O2(SeO3)2Cl2 (georgbokiite and parageorgbokiite), and KCdCu7O2(SeO3)2Cl9 (burnsite)) have been investigated by means of the analysis of their theoretical electron density distributions. The analysis reveals the existence in the structures of two basic types of interactions: intermediate interactions with essential covalent contribution and closed-shell interactions. In Zn2(SeO3)Cl2 polymorphs and burnsite, all metal-oxide and metal-chloride interactions are of the first type, whereas in georgbokiite and parageorgbokiite, the Jahn–Teller distortion results in the elongation of some of the Cu–X bonds and their transition to the closed-shell type. All anion–anion interactions are of the closed-shell type. The energy of the closed-shell Se–Cl interactions can be estimated as 1.4–2.6 kcal.mol−1, which is comparable to weak hydrogen bonds. Despite their weakness, these interactions provide additional stabilization of structural architectures. The Se4+–Cl− configurations are localized inside framework channels or cavities, which can be therefore be viewed as regions of weak and soft interactions in the structure. [ABSTRACT FROM AUTHOR]

Single crystals of the new copper selenate Cu3(SeO4)2(SeO3OH)2 (H2O)16 are obtained by hydrothermal reaction of an aqueous solution of (UO2)NO3, Cu(NO3)2, and H2SeO4 (autoclave, 180 °C, 72 h) followed by slow solvent evaporation. [ABSTRACT FROM AUTHOR]