Synthesis, crystal structure and magnetic properties of a Cu^II–W^V/IVbimetallic complex with a novel open framework structure

Abstract

Fabricated by cyano-and alkoxyl-bridged groups, a novel three-dimensional structural compound,, has been formed. In the structure, there exist two kinds of W atoms and three types of Cu 2 O 2 pairs. The W(1) and W(2) atoms, with oxidation states ϩ5 and ϩ4 respectively, are each linked to the Cu 2 O 2 units through two of its eight cyanide ligands, forming two kinds of 1D zigzag chain along the c-axis (nominally the W1-chain and the W2-chain). Each W2-chain is connected to four adjacent W1-chains through a third type of Cu 2 O 2 unit, leading to the formation of a three-dimensional open framework with channels generated along the [001] direction. The structure may also be viewed as being constructed from W(1)Cu 3 and W(2)Cu 4 clusters, cross-linked by µ-O bridges. The magnetic properties show that the complex displays 3D antiferromagnetic ordering below 2.2 K, although ferromagnetic interactions are present within the W(1)Cu 3 clusters. The dominant antiferromagnetic coupling at low temperature is attributed to the antiferromagnetic exchanges between the W(1)Cu 3 clusters through the alkoxyl bridges.

Exploring the formation of 3D ferromagnetic cyano-bridged CuII2+x{CuII4[WV(CN)8]4–2x[WIV(CN)8]2x}·yH2O networks

“…The strong interest in the design and construction of magnetic molecular materials has drawn much attention to 2D and 3D cyano-bridged copper-octacyanometalate (M = Mo, W) coordination networks. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] The effective coupling along the M V -CN-Cu II linkage resulted in systems exhibiting long range magnetic ordering including examples of low temperature metamagnets. [1][2][3][4][5] The optical metal-to-metal charge transfer (MMCT) from [Mo IV (CN) 8 ] 42 to Cu II moieties offered an opportunity to construct photomagnetic high-spin molecules as well as 3D systems characterised by reversible photoswitching between {Cu II Mo IV Cu II } and {Cu I Mo V Cu II } magnetic states.…”

“…1,[6][7][8][9] The diversity of cyano-bridged Cu II M V/IV coordination architectures is an outcome of the variety of synthetic strategies employed. Several building block approaches were applied, including the direct combination of molecular precursors, 1,4,6,7,[10][11][12][13][14][15][16]19 the use of assisting organic or inorganic molecules as blocking ligands, 2,17 bridging spacers 10,18 or counterions 3,9,10,17 along with the electrochemical synthesis 9 of a 3D Cs 2 Cu II 7 [Mo IV (CN) 8 ] 4 ?6H 2 O network with the use of a standard three-electrode set-up. Some examples of synthetic procedures highlight the unquestionable role of dynamic or/ and static control of the competitive reactions (i.e.…”

In Situ Construction of Interface with Photothermal and Mutual Catalytic Effect for Efficient Solar‐Driven Reversible Hydrogen Storage of MgH2

“…After the reversible hydrogenation process, characteristic peaks belonging to Ti─H bonds at 453 and 459.8 eV could be found with the absence of Ti, confirming the reversible formation of Ti/TiH 2 species during the cycling process of MgH 2 . High‐resolution Ti 2 p and N 1 s XPS results of MgH 2 catalyzed by TNT5 at different states (Figure S19 , Supporting Information) demonstrate that the characteristic peaks of TiN and TiN x O y [ 19 ] inside of TNT5 could be well‐preserved throughout the reversible hydrogen storage process. This result demonstrates the in situ reversible formation of Ti/TiH 2 and the well‐preservation of TiN and TiN x O y upon repeated H 2 desorption and adsorption process that could play a catalytic effect in improving the hydrogen storage performance of MgH 2 .…”

Integration of Trinuclear Triangle Copper(II) Secondary Building Units in Octacyanidometallates(IV)-Based Frameworks

“…SBUs are occasionally used to construct extended polycyanidometallate-based systems. Of the over 600 records in the Cambridge Structural Database (CSD v2020.2.0), SBU elements are found in a small percentage of octacyanidometallate-bridged coordination polymers. − Octacyanidometallate-bridged coordination polymers represent the most abundant and structurally diverse family of compounds within polycyanidometallate-based systems. , Only four three-dimensional (3D) networks ,, and five two-dimensional (2D) layered systems have been reported. ,, The most utilized SBUs (Figure ) can be assigned to Ru 2 L 4 paddlewheels, , M′ 9 W 6 L 24 (M′ = Mn, Co) six-capped body-centered cube clusters, , multicenter copper­(II) units (Cu n L m , where n : m = 2:2, 3:4, and 4:4), − binuclear nickel­(II)-lanthanide­(III) nodes (NiLnL), , and polynuclear copper­(II)-lanthanide­(III) nodes (Cu n LnL m , where n : m = 1:1, 2:2, and 3:1) − with diverse organic and inorganic ligands (L). It is noteworthy that all SBUs, excluding Co 9 W 6 L 24 clusters, have two to four positions capable of forming coordination bonds with cyanides.…”