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The preparation of new geometrically spin-frustrated magnetic materials [1] that approximate theoretical models [1,2] is a challenge. Although the Mermin-Wagner theorem [3] indicates that long-range magnetic order can exist in two dimensions at zero Kelvin, order can be destroyed either by quantum fluctuations or geometric frustration even at this temperature. Theoretical studies indicate that the ground state of a spin-1/2 Heisenberg antiferromagnet is most likely to be semiclassically ordered.[4] However, the interplay of geometric frustration and quantum fluctuations has been found to give rise to a paramagnetic ground state without semi-classical long-range order in two types of lattice.The first of these lattices is the famous KagomØ lattice (T8) and the second is the so-called "star" lattice (T9; Scheme 1), which may serve as a new example of a quantum paramagnet. [4,5] The triangles are corner-sharing in the KagomØ lattice whereas they are separated by a bridge in the star lattice, which means that their next-nearest-neighbor exchange interactions are different. [4,5] The magnetic J exchange pathways in the KagomØ lattice are all equivalent, whereas the intra-triangular J T pathway in the star lattice is weaker than the inter-triangular J D pathway. In contrast to the rapid development of KagomØ-type antiferromagetic lattices [6, 7] and related, geometrically spin-frustrated lattices, [8] there appears to date to be no report of a compound with a genuine star lattice. [7][8][9] including the desired magnetically frustrated star lattice. This star lattice can be described in vertex notation as 3.12 2 (see Scheme S1 in the Supporting Information), a lattice that is a uniform, three-connected twodimensional net with large voids.[10] Three-connected node subunits that prefer to bond in a planar fashion, such as the basic cationic iron(III) carboxylate cluster [Fe 3 [11] where L may be water, methanol, or pyridine, must be used to avoid three-dimensional connections. These carboxylate clusters are good potential building blocks because they are easily prepared, prefer planar bonding, and the R groups and L ligands can easily be varied. [12] The cationic [Fe 3 + moiety has previously served as a six-or three-connected node (see Scheme S2 in the Supporting Information) to form either three- [12a-e] or zero-dimensional [12f] porous frameworks depending upon the nature of the carboxylate, which may be either fully or partially substituted by dicarboxylates; the L ligands are usually retained as terminal ligands. Although no example is known to date, it should be possible to substitute the L ligands located in the triangular [Fe 3

Being bulky is good: The use of a bulky multifunctional ligand is key to the successful construction of a neutral 3D copper coordination polymer that shows 1D open channels and the first interpenetrating NbO‐type network (see picture). The absorption properties of the complex are investigated.

A staggered arrangement like that of the hydrogen atoms in ethane is exhibited by the six phenol groups about each pair of silver atoms in the self-assembled three-dimensional coordination networks [Ag(2)(H(2)L)(3)](n)X(2n) (H(2)L=N,N'-bis(salicylidene)-1,4-diaminobutane; X(-)=NO(3)(-) or ClO(4)(-)); the former is depicted (for clarity the H(2)L ligands are represented by long rods and the Ag atoms by hatched circles). These solids contain short ligand-unsupported metal-metal bonds and display intense blue photoluminescence at room temperature.

Three interesting coordination polymers, [Ag4(μ4-hmt)(μ4-η2-nda)2]·2H2O (1), [Ag2(μ-hmt)2(μ-bi-η2-bna)]·2H2O·MeCN (2), and [Ag2(μ4-hmt)(η2-hna)(MeCN)](hna)·H2O (3) (hmt = hexamethylenetetramine, nda = 2,6-naphthalenedicarboxylate, bna = 2,2‘-dihydroxy-1,1‘-binaphthalene-3,3‘-dicarboxylate, and hna = 1-hydroxy-2-naphthalenecarboxylate), were obtained from the reaction of silver(I) aromatic carboxylates in MeCN solution with hmt in CH2Cl2 solution via the liquid diffusion method. In these complexes, the aromatic carboxylates ligate to the metal atoms via a unique η2-coordination mode involving their aromatic rings, in addition to the normal coordination modes utilizing their carboxylate oxygen atoms. These complexes show interesting electronic properties similar to those reported for the silver(I) complexes of other polycyclic aromatic compounds. Both 1 and 2 exhibit a strong blue photoluminescence at room temperature.

Abstract:The pentagonal bipyramidal single-ion magnets (SIMs) are among the most attractive prototypes of high performance single-molecule magnets (SMMs). Here we introduced the fluorescence-active phosphine oxide ligand, combing the dynamic magnetic measurement, optical characterization and ab initio calculation, firstly studied the magneto-optical correlation of a highperformance pseudo-D5h Dy(III) SIM with large Ueff = 508(2) K and high magnetic hysteresis temperature of 19 K, [Dy(CyPh2PO)2(H2O)5]Br3· 2(CyPh2PO)· EtOH· 3H2O (CyPh2PO = cyclohexyl(diphenyl)phosphine oxide). This work shall provide a deeper insight into the rational design of promising molecular magnets.

Two compounds, [Ag(2,4‘-bpy)]NO3 (1) and [Ag(2,4‘-bpy)]ClO4 (2), were obtained from self-assembly of AgX (X = NO3 -, ClO4 -) with 2,4‘-bipyridine (2,4‘-bpy). 1 crystallizes in the orthorhombic space group Pbca, with a = 11.2884(7) Å, b = 11.3981(10) Å, c = 16.5299(13) Å, and Z = 8, while 2 crystallizes in the monoclinic space group P21 /c, with a = 10.6361(4) Å, b = 9.9896(4) Å, c = 11.2661(6) Å, β = 98.527(4)°, and Z = 4. Both complexes consist of helical [Ag(2,4‘-bpy)]∞ chains that are surrounded by nitrate or perchlorate counterions. Adjacent helical chains are racemic. The AgI atom is linked to two nitrogen atoms of the 2-pyridyl and 4‘-pyridyl groups from two different 2,4‘-bpy ligands as well as to the oxygen atom of the counterion. In 1, another oxygen atom of the counterion is weakly coordinated to the AgI atom of an adjacent chain, thus bridging the helical chains into a wavy 2-D network structure, whereas in 2, adjacent helical chains are linked by the weak ligand-unsupported metal−metal interactions, resulting in an open 2-D network with compressed hexagons as building units. The structures of 1 and 2 imply the role that counterions may play in the framework construction.