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The crystal structure of the title salt, C20H42N42+·2ClO4−, has been determined using synchrotron radiation at 220 (2) K. The structure determination reveals that protonation has occurred at diagonally opposite amine N atoms. The asymmetric unit comprises one half of the organic dication, which lies about a center of inversion, and one perchlorate anion. The macrocyclic dication adopts the most stable endodentate trans-III conformation. The crystal structure is stabilized by intra­molecular N—H...N, and inter­molecular N—H...O and C–H...O hydrogen bonds involving the macrocycle N—H and C—H groups as donors and the O atoms of perchlorate anions as acceptors, giving rise to a three-dimensional network. [ABSTRACT FROM AUTHOR]

The crystal structure of the hydrated title salt, C22H48N44+4Cl-4H2O(C22H48N4 =H4L = 3,14-diethyl-2,6,13,17-tetraazoniatricyclo[16.4.0.07,12]docosane), has been determined using synchrotron radiation at 220 K. The structure determination reveals that protonation has occurred at all four amine N atoms. The asymmetric unit comprises one half of the macrocyclic cation (completed by crystallographic inversion symmetry), two chloride anions and two water molecules. The macrocyclic ring of the tetracation adopts an exodentate (3,4,3,4)-D conformation. The crystal structure is stabilized by intermolecular hydrogen bonds involving the macrocycle N-H groups and water O-H groups as donors, and the O atoms of the water molecules and chloride anions as acceptors, giving rise to a three-dimensional network. [ABSTRACT FROM AUTHOR]

The crystal structure of title compound, (C14H36N4)[CrO3Cl]2Cl2, has been determined by synchrotron radiation X-ray crystallography at 220 K. The macrocyclic cation lies across a crystallographic inversion center and hence the asymmetric unit contains one half of the organic cation, one chlorochromate anion and one chloride anion. Both the Cl- anion and chlorochromate Cl atom are involved in hydrogen bonding. In the crystal, hydrogen bonds involving the 1,4,8,11-tetramethyl-1,4,8,11-tetraazoniacyclotetradecane (TMC) N--H groups and C--H groups as donor groups and three O atoms of the chlorochromate and the chloride anion as acceptor groups link the components, giving rise to a threedimensional network. [ABSTRACT FROM AUTHOR]

The crystal structure of title salt, C14H36N44+·2ClO4-·2Cl-, has been determined using synchrotron radiation at 220-K. The structure determination reveals that protonation has occurred at all four amine N atoms. The asymmetric unit contains one half-cation (completed by crystallographic inversion symmetry), one perchlorate anion and one chloride anion. A distortion of the perchlorate anion is due to its involvement in hydrogen-bonding interactions with the cations. The crystal structure is consolidated by intermolecular hydrogen bonds involving the 1,4,8,11-tetramethyl-1,4,8,11-tetraazoniacyclotetradecane N-H and C-H groups as donor groups, and the O atoms of the perchlorate and chloride anion as acceptor groups, giving rise to a three-dimensional network. [ABSTRACT FROM AUTHOR]

The crystal structure of title salt, C22H46N42+·2NO3−·2H2O, has been determined using synchrotron radiation at 220 K. The structure determination reveals that protonation has occurred at diagonally opposite amine N atoms. The asymmetric unit contains half a centrosymmetric dication, one nitrate anion and one water mol­ecule. The mol­ecular dication, C22H46N42+, together with the nitrate anion and hydrate water mol­ecule are involved in an extensive range of hydrogen bonds. The mol­ecule is stabilized, as is the conformation of the dication, by forming inter­molecular N—H⋯O, O—H⋯O, together with intra­molecular N—H⋯N hydrogen bonds. [ABSTRACT FROM AUTHOR]

The structure of the title compound, [Cr(tacn)2]2[ZnCl4]3·H2O (tacn is 1,4,7-tri­aza­cyclo­nonane; C6H15N3), has been determined from synchrotron X-ray data. Each CrIII cation is coordinated by the six N atoms from the two tacn ligands, displaying a distorted octa­hedral geometry. Three distorted tetra­hedral [ZnCl4]2− anions and one lattice water mol­ecule lie outside this coordination sphere. The Cr—N bond lengths are in the range 2.0621 (11) to 2.0851 (12) Å, while the mean inner N—Cr—N bond angle is 82.51 (5)°. The crystal packing is stabilized by hydrogen-bonding inter­actions with the N—H groups of the tacn ligands and the water O—H groups acting as donors, and the O atoms of the water mol­ecules and Cl atoms of the [ZnCl4]2− anions as acceptors. Overall these contacts lead to the formation of a three-dimensional network. [ABSTRACT FROM AUTHOR]

Triphenylamine (TPA), a propeller-shaped optoelectronic molecule, has been used to generate stimuli-responsive smart fluorescent organic materials and correlate the effect of subtle structural changes on the molecular packing and mechanochromic fluorescence (MCF). The substituent (OCH3) position in the TPA phenyl ring and acceptors (malononitrile, cyanoacetamide, cyanoacetic acid, ethyl cyanoacetate, and diethylmalonate) strongly influenced the solid state and mechanochromic fluorescence as well as the molecular packing. The structure-property studies revealed that (i) TPA derivatives without the OCH3 substituent exhibit strong fluorescence (ϕf = 85% (TCAAD-1, 55% (TDEM)), (ii) higher dihedral angle (τ) between donor (aminophenyl) and acceptor lead to weak/non fluorescent material, (iii) substituent at the ortho position to acceptor increased the dihedral angle (τ = 26.49 (TCAAD-2), τ = 27.14 (TDMM)), and (iv) the increase of alkyl groups produced self-reversible high contrast off-on fluorescence switching materials (TDEM). Powder X-ray diffraction studies indicate that stimuli induced reversible phase transformation from crystalline to amorphous and vice versa was responsible for fluorescence switching. The computational studies also supported that OCH3 substitution at ortho to acceptor increased the dihedral angle and optical band gap. Thus, the present studies provide a structural insight for designing TPA based organic molecules for developing new smart organic materials. Stimuli responsive smart fluorescent triphenylamine derivatives have been synthesized that exhibited reversible and self-reversible mechanochromism, and nonfluorescence solids depend on the position of substitution and acceptor structure. [ABSTRACT FROM AUTHOR]