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A water-mediated transformation reversibly converts the neutral 3D microporous coordination polymers [Ln(2)(adipate)(3)(-)(H(2)O)(4)]center dot 6H(2)O (Ln(3+) = Pr(3+)) and [Ln(2)(adipate)(3)(H(2)O)(4)]xH(2)O (Ln(3+) = Gd(3+), Sm(3+)), into the ionic 1D polymer [Ln(adipate)(H(2)O)(5)]XH(2)O (with X = NO(3)(-), Cl(-) and Ln(3+) = Pr(3+), Gd(3+), Sm(3+)). The 1D polymer consists of positively charged hydrogen-bonded lanthanide-adipate chains enclathrating NO(3)(-) or Cl(-) anions acting as templates. The hydrogen bonds linking the chains between them are so strong, that it is possible to exchange NO(3)(-) for Cl(-) and vice versa in a crystal-to-crystal manner. The anion exchange reactions were directly observed oil crystals by Using Raman microprobe spectroscopy, single-crystal X-ray diffraction, and scanning electron microscopy. Crystal Growth & Design

Organotin(IV) complexes with the formulas [(C(6)H(5))(3)Sn(mbzt)] (1), [(C(6)H(5))(3)Sn(cmbzt)] (3), and [(C(6)H(5))(2)Sn(cmbzt)(2)] (4) (Hmbzt = 2-mercaptobenzothiazole and Hcmbzt = 5-chloro-2-mercaptobenzothiazole) have been synthesized and characterized by elemental analysis; FT-IR, Raman, (1)H, (13)C, and (119)Sn NMR, and Mossbauer spectroscopic techniques; and X-ray crystallography at various temperatures. The crystal structures of complexes 1, 3, and 4 were determined by X-ray diffraction at room temperature [295(1) or 293(2) K]. The complexes [(C(6)H(5))(3)Sn(mbzo)] (2) and [(n-C(4)H(9))(2)Sn(cmbzt)(2)] (5) (Hmbzo = 2-mercaptobenzoxazole) were synthesized by new improved methods, and their structures were determined at low temperature [100(1) K] and compared to those solved at room temperature. Comparison with {(CH(3))(2)Sn(cmbzt)(2)]} (6), already reported, was also attempted. The influence of temperature on the geometry of the complexes is discussed. In the cases of complexes 1-3, three carbon atoms from phenyl groups and one sulfur atom and one nitrogen atom from thione ligands form a tetrahedrally distorted trigonal-bipyramidal geometry around the five-coordinate tin(IV) ion. In complexes 4-6, two carbon atoms from aryl groups and two sulfur atoms and two nitrogen atoms from thione ligands form a distorted tetrahedral geometry, tending toward octahedral, around the six-coordinate tin(IV) ions, with trans-C(2), cis-N(2), and cis-S(2) configurations. Although the C-Sn and S-Sn bond distances are found to be constant in compounds 1-6, their N-Sn bond lengths vary significantly (from 2.635 to 3.078 angstrom), with the longer distances found in the cases of five-coordinate complexes 1-3. Inorg Chem

The self-assembly of four symmetrically substituted tri-aryl-benzene derivatives of formula C24H15X3, where X = H (1), Cl (2), COOMe (3), and COOH (4), was studied as a function of the substituent X. Crystal packing analysis of compounds 1-3 showed that in 1, there are no strong face-to-face stacking interactions, whereas in both compounds 2 and 3, molecular columns were formed, held by numerous "lateral" C-H center dot center dot center dot Cl and C-H center dot center dot center dot O hydrogen bonds, respectively. However, strong intermolecular face-to-face aromatic interactions, appropriate for excimer formation, were observed only in 3, in line with results obtained by fluorescence spectroscopy. The pi-pi aromatic interactions are significantly stronger in the case of the triacid 4, but a lack of adequate single crystals of this compound prevented any detailed study for correlating crystal architecture with fluorescence emission observed. However, FT-IR and TEM experiments showed the existence of dimeric H-bonds and short (0.35 nm) distances between the phenyl rings. Crystal Growth & Design

Two isostructural coordination polymers of formula [Ln(2)(ADC)(3)(H2O)(6)]center dot 2H(2)O, (ADC = acetyledicarboxylato dianion, Ln(3+) = La3+ or Ce3+) have been prepared at room temperature. The structure is three-dimensional, possessing one-dimensional channels filled with lattice and coordinated water molecules. The presence of three water molecules in the coordination sphere of the metal creates a dense hydrogen-bonded network. The lattice water molecules were removed from the cerium compound at 100 T with retention of the structure. This transformation was also possible in a crystal-to-crystal manner. The structure of the dehydrated solid was determined and found to present only minor modifications compared to the parent structure. The departure of the coordinated water molecules is carried out in three steps, with retention of the structure up to 150 degrees C. Beyond this temperature, dehydration is accompanied by polymerization, due to the existence of an infinite chain of short acetylene-acetylene contacts. Crystal Growth & Design

The novel one-dimensional coordination polymer [Cd(ADC)(H2O)(3)] H2O, where ADC(2-) = acetylenedicarboxylate dianion, was synthesized and characterized by single-crystal X-ray diffraction. The titled compound crystallizes in the monoclinic system, P2(1)/n, a = 6.908(1) Angstrom, b = 7.946(1) Angstrom, c = 16.390(1) Angstrom, beta = 100.21(1)degrees, V = 885.4(2) Angstrom(3), and Z = 4. The structure is made up of metal-organic chains linked by hydrogen bonds to form channels along the b axis. The carbon-carbon triple bonds are in close proximity (3.27 Angstrom) along the a axis. This induces, upon heating, polymerization with formation of conjugated polycarboxylic chains. Detailed EPR studies have been performed in order to understand the polymerization process. Chemistry of Materials