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Jan Janczak

Publications and source records attributed to Jan Janczak.

At least 19 recordsLinked to original sources
PubMed2006

Tetrakis[phthalocyaninato(2-)antimony(III)] docosaiodohexaantimony(III).

Crystals of a novel antimony(III)-phthalocyanine complex, [Sb(C(32)H(16)N(8))](4)[Sb(6)I(22)] or [SbPc](4)[Sb(6)I(22)], where Pc is the phthalocyaninate(2-) macrocycle, have been obtained from the reaction of pure powdered antimony with phthalonitrile under oxidation conditions of iodine vapour at 533 K. The crystal structure is built up from separate but interacting [SbPc](+) cations and [Sb(6)I(22)](4-) anions. Each Sb atom of the two independent [SbPc](+) cations is bonded to the four isoindole N atoms of the Pc macrocycle and lies 0.986 (1) A out of the plane defined by these N atoms. The anion consists of six distorted SbI(6) octahedra linked via bridging I atoms into a centrosymmetric [Sb(6)I(22)](4-) anion. The arrangement of the oppositely charged species, viz. [SbPc](+) and [Sb(6)I(22)](4-), in the crystal structure is determined mainly by the ionic attractions between the ions, forming a centrosymmetric [(SbPc)(4)(Sb(6)I(22))] unit. Neighbouring [(SbPc)(4)(Sb(6)I(22))] units related by translation interact via pi-pi interactions between the aromatic macrocycles in a back-to-back fashion.

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PubMed2006

Two crystals of doubly protonated melaminium salts: melaminium bis(trifluoroacetate) trihydrate and melaminium bis(trichloroacetate) dihydrate.

Crystals of 2,4,6-triamino-1,3,5-triazine-1,3-dium bis(trifluoroacetate) trihydrate, C(3)H(8)N(6)(2+)x2CF(3)COO(-)x3H(2)O, and 2,4,6-triamino-1,3,5-triazine-1,3-dium bis(trichloroacetate) dihydrate, C(3)H(8)N(6)(2+)x2CCl(3)COO(-)x2H(2)O, both contain doubly protonated melamine rings that lie on crystallographic twofold axes. In the former structure, one water molecule also lies on a twofold axis. While the trifluoroacetate compound crystallizes in a centrosymmetric space group, the trichloroacetate is non-centrosymmetric, so it is useful as a material for non-linear optics. The efficiency of second harmonic generation is about three times greater than that of KDP (KH(2)PO(4)). A combination of ionic and donor-acceptor hydrogen-bond interactions link the melaminium(2+) residues with trifluoroacetate or trichloroacetate ions and water molecules to form a three-dimensional network.

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PubMed2006

Bis{[phthalocyaninato(2-)]arsenic(III)} octaiododiarsenic(III).

Crystals of the novel title arsenic(III)-phthalocyanine complex, [As(C32H16N8)]2[As2I8] or [AsPc]2[As2I8], where Pc is the phthalocyaninate(2-) macrocycle, have been obtained from the reaction of pure powdered arsenic with phthalonitrile under oxidizing conditions (iodine vapour) at 463 K. The crystals are formed by separate but interacting [AsPc]+ cations and centrosymmetric [As2I8]2- anions. The As atom of the [AsPc]+ ion is bonded to the four isoindole N atoms of the Pc macrocycle and lies 0.762 (1) A out of their plane. The anionic part of the complex consists of two [AsI4]- units joined together into a centrosymmetric [As2I8]2- counter-ion. The arrangement of oppositely charged moieties, viz. [AsPc]+ and [As2I8]2-, in the crystal structure is determined mainly by their ionic attractions and by pi-pi interactions between the aromatic phthalocyaninate(2-) macrocycles.

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PubMed2005

Tetramethylammonium 2,5-dinitrophenolate monohydrate.

The crystal structure of the title compound, C4H12N+.C6H3N2O5-.H2O, is built up from tetramethylammonium cations, 2,5-dinitrophenolate anions and water molecules. The nitro groups are almost coplanar with the aryl ring, which exhibits significant distortion from an ideal hexagonal form. The X-ray geometry of the tetramethylammonium cation shows slight distortion from the tetrahedral symmetry predicted by molecular orbital calculations. The O-H...O hydrogen-bonded water and 2,5-dinitrophenolate units are related by an inversion center and form dimers. The 2,5-dinitrophenolate anions, related by an inversion center and translation, are stacked to form a column along the [100] direction.

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PubMed2004

Iodo[phthalocyaninato(2-)]manganese(III) bridged by a neutral I2 molecule.

The title manganese(III) phthalocyaninate (Pc) complex, viz. iodo[phthalocyaninato(2-)]manganese(III) hemi(diiodine), [Mn(C32H16N8)I].0.5I2 or (MnPcI)2.I2, was obtained from the reaction of pure powdered manganese with phthalonitrile under oxidation conditions of iodine vapour. The phthalocyaninato(2-) residue is not strictly planar and the Mn atom is five-coordinate, having distorted square-pyramidal geometry and residing 0.262 (2) A above the plane defined by the four isoindole N atoms of the phthalocyaninate macrocycle. The neutral I2 molecule bridges the iodo[phthalocyaninato(2-)]manganese(III) molecules, forming a centrosymmetric dimeric structure.

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PubMed2004

Melaminium maleate monohydrate.

In the title compound, 2,4,6-triamino-1,3,5-triazin-1-ium maleate monohydrate, C3H7N6+.C4H3O4-.H2O, containing singly protonated melaminium residues, maleate(1-) anions and water molecules, the components are linked by hydrogen bonds into a three-dimensional framework structure. The melaminium residues are connected by two pairs of N-H...N hydrogen bonds into chains in the form of stacks, with a distance of 3.26 (1) A between the triazine rings, clearly indicating pi-pi interactions. The maleate anion contains an intramolecular O-H...O hydrogen bond and the anions interact with the water molecules via O-H...O hydrogen bonds, forming zigzag chains, also in the form of stacks, in which the almost-planar maleate anions are separated by 3.26 (1) A. The experimental geometries of the ions are compared with molecular-orbital calculations of their gas-phase geometries.

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PubMed2003

Anilinium monohydrogen DL-malate.

Crystals of the title salt, [(C(6)H(5)NH(3))](+).[(HOOC(CH(2))CH(OH)COO)](-) or C(6)H(8)N(+).C(4)H(5)O(5)(-), are built up from protonated anilinium residues and monodissociated DL-malate ions. The NH(3)(+) group of the anilinium cation is ordered at room temperature. Rotation of the NH(3)(+) group along the C(aromatic)-Nsp(3) bond (often observed at room temperature in other anilinium salts) is prevented by N-H.O hydrogen bonds between the NH(3)(+) group and the malate anions. The anions are connected by four O-H.O hydrogen bonds into two-dimensional sheets parallel to the (001) plane. The charged moieties, i.e. the anilinium cations and the sheets of hydrogen-bonded malate anions, form two-dimensional layers in which the phenyl rings of the anilinium residues lie perpendicular to the malate-ion sheets. The conformation of the monodissociated malate ion in the crystal is compared with that obtained from ab initio molecular-orbital calculations.

Aniline Compounds↗
PubMed2003

2-(3-pyridyl)-1,3,8-triazanaphthalene, a product of the catalytic transformation of 3-cyanopyridine.

The title compound, C(12)H(8)N(4), was obtained by thermal treatment of 3-cyanopyridine in the presence of magnesium phthalocyanine as catalyst. The X-ray structure analysis, in direct contrast to molecular orbital calculations corresponding to the gas phase, shows the molecule to be non-planar in the solid state, with an interplanar angle between the pyridine and 1,3,8-triazanaphthalene rings of 13.33 (9) degrees. Molecules related to one another by cell translation, and positioned at intervals consistent with pi-pi intermolecular interactions, form stacks in the b direction.

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PubMed2003

Synthesis, structural investigation, and solid-state properties of iodine-doped zirconium diphthalocyanine, [ZrPc2]I3.I2.

Crystals of iodine-doped zirconium(IV) diphthalocyanine, [ZrPc(2)]I(3).I(2) (where Pc = C(32)H(16)N(8)), were grown directly in the reaction of pure zirconium powder with phthalonitrile under a stream of iodine at 260 degrees C. [ZrPc(2)]I(3).I(2) crystallizes in the space group P2(1)/m (No. 11) of the monoclinic system with lattice parameters of a = 6.735(1), b = 25.023(5), and c = 17.440(3) A, beta = 99.43(3) degrees, and Z = 2. The crystals of [ZrPc(2)]I(3).I(2) are built up from two pseudo-monodimensional aggregates: one-electron-oxidized [ZrPc(2)](+) units; weak interacting triiodide I(3)(-) ions with neutral diiodine molecules. The I(3)(-) ions and neutral I(2) molecules in the crystal of [ZrPc(2)]I(3).I(2) have been also detected by Raman spectroscopy. The [ZrPc(2)](+) units form stacks along the a axis, while the polymeric...I(3)(-)...I(2)...I(3)(-)...I(2)(-)... zigzag chains are located in the crystal along the b axis, so both pseudo-monodimensional aggregates are perpendicular to each other. This arrangement is different from that found in the tetragonal crystals of [ZrPc(2)](I(3))(2/3) in which both monodimensional aggregates, i.e., the stacks of partially oxidized [ZrPc(2)](2/3+) units and chains of symmetric triiodide ions, are parallel. EPR experiment together with the X-ray single-crystal analysis clearly shown that oxidation of the diamagnetic ZrPc(2) complex by iodine is ligand centered and homogeneously affecting both phthalocyaninato rings of ZrPc(2); thus, the formal oxidation state of both Pc rings in [ZrPc(2)]I(3).I(2) is nonintegral (-1.5). The UV-vis spectrum of [ZrPc(2)] I(3).I(2) is very similar to the spectrum of unoxidized ZrPc(2) complex in the B Soret and Q spectral region. However, in the spectrum of [ZrPc(2)] I(3).I(2) one additional band at approximately 502 nm is observed, which indicates the existence of the one-electron-oxidized phthalocyaninato(-) radical ligand and is assigned to the electronic transition from a deeper level to the half-occupied HOMO level. The single-crystal electrical conductivity data show anisotropy and nonmetallic character in conductivity (d sigma/dT > 0). The charge transport mainly proceeds along the pseudo-monodimensional stacks of [ZrPc(2)](+) units. The relatively high conductivity along the stacks of one-electron-oxidized [ZrPc(2)](+) units results from the staggering orientation of Pc rings (rotation angle 45.0(2) degrees ) that leads to the short inter-ring C(alpha)(pyrrole)[bond]C(alpha)(pyrrole) contacts (2.839(3)-3.024(3) A). These C(alpha)-pyrrole atoms make appreciable contribution to the partially occupied pi-molecular orbital of Pc macrocycle and the greatest overlap of the HOMO orbitals that form the conduction band of partially oxidized molecular crystals.

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PubMed2003

Two isomorphous complexes: dichloro[phthalocyaninato(2-)]tin(IV) and dichloro[phthalocyaninato(2-)]germanium(IV).

Isomorphous triclinic forms of dichloro[phthalocyaninato(2-)]tin(IV), [Sn(C(32)H(16)N(8))Cl(2)], and dichloro[phthalocyaninato(2-)]germanium(IV), [Sn(C(32)H(16)N(8))Cl(2)], and a monoclinic form of the latter have been obtained from the reaction of pure tin and germanium powder, respectively, with phthalonitrile under a stream of ICl vapour. All three crystal structures consist of centrosymmetric [SnPcCl(2)] and [GePcCl(2)] [Pc is phthalocyaninate(2-)] molecules, which are separated but interacting. In the triclinic forms (Sn and Ge), the Pc macrocycles are not staggered but slipped, and in the monoclinic form (Ge), the molecules are additionally inclined. In both cases, the central Sn or Ge atom is six-coordinated by the four isoindole N atoms of the Pc macrocyclic ligand and by two Cl atoms (located trans) into a tetragonal-bipyramidal structure. The arrangement of [SnPcCl(2)] and [GePcCl(2)] molecules in the crystal structure is determined mainly by intermolecular C-H.Cl, pi-pi and van der Waals interactions.

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PubMed2003

Bis(melaminium) DL-malate tetrahydrate.

The crystal structure of the title melaminium salt, bis(2,4,6-triamino-1,3,5-triazin-1-ium) DL-malate tetrahydrate, 2C(3)H(7)N(6)(+).C(4)H(4)O(5)(2-).4H(2)O, consists of singly protonated melaminium residues, DL-malate dianions and water molecules. The melaminium residues are connected into chains by four N-H.N hydrogen bonds, and these chains form a stacking structure along the c axis. The DL-malate dianions form hydrogen-bonded chains and, together with hydrogen-bonded water molecules, form a layer parallel to the (100) plane. The conformation of the malate ion is compared with an ab initio molecular-orbital calculation. The oppositely charged moieties, i.e. the stacks of melaminium chains and hydrogen-bonded DL-malate anions and water molecules, form a three-dimensional polymeric structure, in which N-H.O hydrogen bonds stabilize the stacking.

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PubMed2003

Bis([phthalocyaninato(2-)]arsenic(III)) tetradecaiodotetra-arsenic(III).

Crystals of the novel title arsenic(III) phthalocyanine complex, [As(C(32)H(16)N(8))](2)[As(4)I(14)] or [(AsPc)(+)](2).[As(4)I(14)](2-), where Pc is phthalocyaninate(2-), have been obtained by the reaction of pure powdered As with phthalonitrile under a stream of iodine vapour at 493 K. The crystals are built up of separate but interacting [AsPc](+) cations and [As(4)I(12)](2-) anions. The As atom of the [AsPc](+) unit is bonded to the four isoindole N atoms of the Pc macrocycle and lies 0.743 (2) A out of the plane defined by these four N atoms. The anionic part of the complex consists of AsI(3) and [AsI(4)](-) units joined together into an [As(4)I(14)](2-) anion. The arrangement of the oppositely charged moieties, [AsPc](+) and [As(4)I(14)](2-), in the crystal is determined mainly by ionic attraction and by donor-acceptor interactions between the [AsPc](+) and [As(4)I(14)](2-) ions.

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PubMed2002

Aqua(phthalocyaninato)magnesium.

The title compound, [Mg(C(32)H(16)N(8))(H(2)O)], crystallizes with two MgPc(H(2)O) molecules (Pc is phthalocyaninate) in the asymmetric unit. The geometries of the two molecules are very similar, with the Mg atoms each 4+1-coordinated by four isoindole N atoms at the base and by the O atom of the water molecule. The Mg atoms are displaced by 0.447 (1) and 0.468 (1) A from the basal coordination planes towards the water O atoms. O-H.N hydrogen bonds form dimers stacked along the b axis in a herring-bone fashion.

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PubMed2002

One-dimensional assembling of diiodo[phthalocyaninato(1-)] chromate(III) molecules through neutral I(2) molecules. Alternating ferro- and antiferromagnetic interactions in the metal-radical system.

Crystals of diiodo[phthalocyaninato(1-)] chromate(III) diiodine, CrPcI(2).I(2), were grown directly in the reaction of chromium powder with 1,2-dicyanobenzene under a stream of iodine at about 250 degrees C. The CrPcI(2).I(2) complex crystallizes in the centrosymmetric space group of the triclinic system with one molecule per unit cell, with the cell dimensions a = 7.851(2) A, b = 8.402(2) A, c = 12.668(3) A, alpha = 80.32(3)(o), beta = 74.06(3)(o), gamma = 82.33(3)(o), and V = 788.7(3) A(3). The X-ray single-crystal analysis shows that each of the centrosymmetric CrPcI(2) molecules is bridged by a neutral I(2) molecule (detected also by Raman spectroscopy) and develops a polymeric one-dimensional structure. The magnetic measurements have been carried out in the temperature range 300-2 K. Temperature dependence of the effective magnetic moment, mu(eff), shows the ferro- and antiferromagnetic interactions in the system of the paramagnetic central Cr(3+) ion and surrounding pi-conjugated radical ligand Pc(1-). The conductivity measurement on a polycrystalline sample exhibits weak temperature dependence (dsigma/dT < 0). The UV-vis spectrum exhibits, besides the B- and Q-bands, one additional band assigned to the electronic transition from a deeper level to the half-occupied HOMO level in the one-electron oxidized phthalocyaninato(1-) radical ligand.

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PubMed2002

Hexakis(melaminium) tetrakis(dihydrogenphosphate) monohydrogenphosphate tetrahydrate.

The crystal structure of the new melaminium salt, hexakis(2,4,6-triamino-1,3,5-triazin-1-ium) tetrakis(dihydrogenphosphate) monohydrogenphosphate tetrahydrate, 6C(3)H(7)N(6)(+).4H(2)PO(4)(-).HPO(4)(2-).4H(2)O, is built up from singly protonated melaminium residues, dihydrogenphosphate and monohydrogenphosphate anions, and water molecules. The melaminium residues are interconnected by four N-H...N hydrogen bonds, forming chains along the [001] direction. These chains of melaminium residues form stacks aligned along [100]. The dihydrogenphosphate anions interact with the monohydrogenphosphate anions via the H atoms and, together with hydrogen-bonded dimers of the water molecules, develop layers parallel to the (010) plane. The oppositely charged moieties interact via multiple N-H...O hydrogen bonds that stabilize the stacking structure.

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PubMed2002

3-Amino-1,2,4-triazine.

In the crystal structure of 3-amino-1,2,4-triazine, C(3)H(4)N(4), the molecules form hydrogen-bonded chains that are almost parallel to the b axis (3.2 degrees), and which are inclined to the a and c axes by approximately 21 and approximately 69 degrees, respectively. The distortion of the 1,2,4-triazine ring in the crystal is compared with gas-phase ab initio molecular-orbital calculations.

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PubMed2002

Melaminium glutarate monohydrate.

The crystal structure of the title new melaminium salt, 2,4,6-triamino-1,3,5-triazin-1-ium glutarate monohydrate, C(3)H(7)N(6)(+) x C(5)H(7)O(4)(-) x H(2)O, is built up from singly protonated melaminium residues, mono-dissociated glutarate ions and water molecules. The melaminium residues are interconnected by four N[bond]H...N hydrogen bonds to form chains. These chains of melaminium residues form a stacking structure. The glutarate anions form a hydrogen-bonded zigzag polymer of the form [...HOOC(CH(2))(3)COO...HOOC(CH(2))(3)COO...](n). The oppositely charged moieties, i.e. the melaminium and glutarate chains, form two-dimensional polymeric sheets. These sheets are interconnected by O[bond]H...O hydrogen bonds between the COO(-) moieties and the water molecules, and these hydrogen bonds stabilize the stacking structure.

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