TY - JOUR

T1 - Cs3LiZn2(WO4)4 and Rb3Li2Ga(MoO4)4

T2 - Different filled derivatives of the cation-deficient Cs6Zn5(MoO4)8 structure

AU - Solodovnikov, Sergey F.

AU - Solodovnikova, Zoya A.

AU - Zolotova, Evgeniya S.

AU - Kadyrova, Yulia M.

AU - Savina, Aleksandra A.

AU - Stefanovich, Sergey Yu

AU - Khaikina, Elena G.

PY - 2017/11/1

Y1 - 2017/11/1

N2 - Two new compounds, namely cubic tricaesium lithium dizinc tetrakis(tetraoxotungstate), Cs3LiZn2(WO4)4, and tetragonal trirubidium dilithium gallium tetrakis(tetraoxomolybdate), Rb3Li2Ga(MoO4)4, belong to the structural family of Cs6Zn5(MoO4)8 (space group I3d, Z = 4), with a partially incomplete (Zn5/6□1/6) position. In Cs3LiZn2(WO4)4, this position is fully statistically occupied by (Zn2/3Li1/3), and in Rb3Li2Ga(MoO4)4, the 2Li + Ga atoms are completely ordered in two distinct sites of the space group I2d (Z = 4). In the same way, the crystallographically equivalent A+ cations (A = Cs, Rb) in Cs6Zn5(MoO4)8, Cs3LiZn2(WO4)4 and isostructural A3LiZn2(MoO4)4 and Cs3LiCo2(MoO4)4 are divided into two sites in Rb3Li2Ga(MoO4)4, as in other isostructural A3Li2R(MoO4)4 compounds (AR = TlAl, RbAl, CsAl, CsGa, CsFe). In the title structures, the WO4 and (Zn,Li)O4 or LiO4, GaO4 and MoO4 tetrahedra share corners to form open three-dimensional frameworks with the caesium or rubidium ions occupying cuboctahedral cavities. The tetrahedral frameworks are related to that of mayenite 12CaO·7Al2O3 and isotypic compounds. Comparison of isostructural Cs3MZn2(MoO4)4 (M = Li, Na, Ag) and Cs6Zn5(MoO4)8 shows a decrease of the cubic lattice parameter and an increase in thermal stability with the filling of the vacancies by Li+ in the Zn position of the Cs6Zn5(MoO4)8 structure, while filling of the cation vacancies by larger Na+ or Ag+ ions plays a destabilizing role. The series A3Li2R(MoO4)4 shows second harmonic generation effects compatible with that of β′-Gd2(MoO4)3 and may be considered as nonlinear optical materials with a modest nonlinearity.Cs3LiZn2(WO4)4 and Rb3Li2Ga(MoO4)4 represent two distinct series of filled derivatives of the cation-deficient Cs6Zn5(MoO4)8 structure with three-dimensional tetrahedral frameworks related to that of mayenite 12CaO·7Al2O3. The series of tetragonal A3Li2R(MoO4)4 compounds exhibits second harmonic generation effects compatible with that of β′-Gd2(MoO4)3.

AB - Two new compounds, namely cubic tricaesium lithium dizinc tetrakis(tetraoxotungstate), Cs3LiZn2(WO4)4, and tetragonal trirubidium dilithium gallium tetrakis(tetraoxomolybdate), Rb3Li2Ga(MoO4)4, belong to the structural family of Cs6Zn5(MoO4)8 (space group I3d, Z = 4), with a partially incomplete (Zn5/6□1/6) position. In Cs3LiZn2(WO4)4, this position is fully statistically occupied by (Zn2/3Li1/3), and in Rb3Li2Ga(MoO4)4, the 2Li + Ga atoms are completely ordered in two distinct sites of the space group I2d (Z = 4). In the same way, the crystallographically equivalent A+ cations (A = Cs, Rb) in Cs6Zn5(MoO4)8, Cs3LiZn2(WO4)4 and isostructural A3LiZn2(MoO4)4 and Cs3LiCo2(MoO4)4 are divided into two sites in Rb3Li2Ga(MoO4)4, as in other isostructural A3Li2R(MoO4)4 compounds (AR = TlAl, RbAl, CsAl, CsGa, CsFe). In the title structures, the WO4 and (Zn,Li)O4 or LiO4, GaO4 and MoO4 tetrahedra share corners to form open three-dimensional frameworks with the caesium or rubidium ions occupying cuboctahedral cavities. The tetrahedral frameworks are related to that of mayenite 12CaO·7Al2O3 and isotypic compounds. Comparison of isostructural Cs3MZn2(MoO4)4 (M = Li, Na, Ag) and Cs6Zn5(MoO4)8 shows a decrease of the cubic lattice parameter and an increase in thermal stability with the filling of the vacancies by Li+ in the Zn position of the Cs6Zn5(MoO4)8 structure, while filling of the cation vacancies by larger Na+ or Ag+ ions plays a destabilizing role. The series A3Li2R(MoO4)4 shows second harmonic generation effects compatible with that of β′-Gd2(MoO4)3 and may be considered as nonlinear optical materials with a modest nonlinearity.Cs3LiZn2(WO4)4 and Rb3Li2Ga(MoO4)4 represent two distinct series of filled derivatives of the cation-deficient Cs6Zn5(MoO4)8 structure with three-dimensional tetrahedral frameworks related to that of mayenite 12CaO·7Al2O3. The series of tetragonal A3Li2R(MoO4)4 compounds exhibits second harmonic generation effects compatible with that of β′-Gd2(MoO4)3.

KW - crystal chemistry

KW - crystal structure

KW - filling vacancies

KW - second harmonic generation

KW - structural family

KW - tetrahedral framework

KW - thermal stability

KW - triple molybdate

KW - triple tungstate

KW - LASER CRYSTALS

KW - OXIDE

KW - MOLYBDATES

KW - CRYSTAL-STRUCTURE

KW - CA12AL14O33

KW - ELEMENTS

KW - TUNGSTATES

KW - GROWTH

KW - LITHIUM

UR - http://www.scopus.com/inward/record.url?scp=85032918491&partnerID=8YFLogxK

U2 - 10.1107/S205322961701378X

DO - 10.1107/S205322961701378X

M3 - Article

C2 - 29111524

AN - SCOPUS:85032918491

VL - 73

SP - 946

EP - 952

JO - Acta Crystallographica Section C: Structural Chemistry

JF - Acta Crystallographica Section C: Structural Chemistry

SN - 2053-2296

IS - 11

ER -