Особливості реалізації графічного конвеєру при візуалізації тривимірних моделей приміщень університету

В більшості систем комп‘ютерної графіки застосовується графічний конвеєр – логічна група послідовно виконуваних обчислень (етапів), які в результаті дають синтезовану сцену на екрані комп‘ютера. Серед основних – етапи геометричних перетворень та візуалізації. Результат виконання кожного з цих етапів впливає на кінцевий вигляд синтезованої сцени, тому їх коректне завершення є необхідною умовою отримання якісного зображення

Molecular Engineering To Control the Magnetic Interaction between Single-Chain Magnets Assembled in a Two-Dimensional Network

Two two-dimensional (2D) systems having the formula [{Fe^III(dmbpy)­(CN)₄}₂Co^IIL]_<i>n</i> [L = pyetNO (<b>1</b>), tvpNO (<b>2</b>)] and consisting of single-chain magnets connected through organic ligands (L) have been prepared, and their magnetic properties have been investigated. The overall magnetic behavior depends on the capacity of the organic pillars to transmit long-range magnetic interactions. <b>1</b> is the first example of a 2D compound exhibiting double relaxation of the magnetization, whereas <b>2</b> behaves as a metamagnet

Double Interpenetration in a Chiral Three-Dimensional Magnet with a (10,3)‑a Structure

A unique chiral three-dimensional magnet with an overall racemic double-interpenetrated (10,3)-a structure of the formula [(<i>S</i>)-(1-PhEt)­Me₃N]₄[Mn₄Cu₆(Et₂pma)₁₂]­(DMSO)₃]·3DMSO·5H₂O (<b>1</b>; Et₂pma = <i>N</i>-2,6-diethylphenyloxamate) has been synthesized by the self-assembly of a mononuclear copper­(II) complex acting as a metalloligand toward Mn^II ions in the presence of a chiral cationic auxiliary, constituting the first oxamato-based chiral coordination polymer exhibiting long-range magnetic ordering

Molecular Engineering To Control the Magnetic Interaction between Single-Chain Magnets Assembled in a Two-Dimensional Network

Two two-dimensional (2D) systems having the formula [{Fe^III(dmbpy)­(CN)₄}₂Co^IIL]_<i>n</i> [L = pyetNO (<b>1</b>), tvpNO (<b>2</b>)] and consisting of single-chain magnets connected through organic ligands (L) have been prepared, and their magnetic properties have been investigated. The overall magnetic behavior depends on the capacity of the organic pillars to transmit long-range magnetic interactions. <b>1</b> is the first example of a 2D compound exhibiting double relaxation of the magnetization, whereas <b>2</b> behaves as a metamagnet

Molecular Engineering To Control the Magnetic Interaction between Single-Chain Magnets Assembled in a Two-Dimensional Network

Two two-dimensional (2D) systems having the formula [{Fe^III(dmbpy)­(CN)₄}₂Co^IIL]_<i>n</i> [L = pyetNO (<b>1</b>), tvpNO (<b>2</b>)] and consisting of single-chain magnets connected through organic ligands (L) have been prepared, and their magnetic properties have been investigated. The overall magnetic behavior depends on the capacity of the organic pillars to transmit long-range magnetic interactions. <b>1</b> is the first example of a 2D compound exhibiting double relaxation of the magnetization, whereas <b>2</b> behaves as a metamagnet

Cation Exchange in Dynamic 3D Porous Magnets: Improvement of the Physical Properties

We report two novel three-dimensional porous coordination polymers (PCPs) of formulas Li₄{Mn₄[Cu₂(Me₃mpba)₂]₃}·68H₂O (<b>2</b>) and K₄{Mn₄[Cu₂(Me₃mpba)₂]₃}·69H₂O (<b>3</b>) obtainedvia alkali cation exchange in a single-crystal to single-crystal processfrom the earlier reported anionic manganese­(II)–copper­(II) PCP of formula Na₄{Mn₄[Cu₂(Me₃mpba)₂]₃}·60H₂O (<b>1</b>) [Me₃mpba^4– = <i>N,N</i>′-2,4,6-trimethyl-1,3-phenylenebis­(oxamate)]. This postsynthetic process succeeds where the direct synthesis in solution from the corresponding building blocks fails and affords significantly more robust PCPs with enhanced magnetic properties [long-range 3D magnetic ordering temperatures for the dehydrated phases (<b>1</b>′–<b>3</b>′) of 2.0 (<b>1</b>′), 12.0 (<b>2</b>′), and 20.0 K (<b>3</b>′)]. Changes in the adsorptive properties upon postsynthetic exchange suggest that the nature, electrostatic properties, mobility, and location of the cations within the framework are crucial for the enhanced structural stability. Overall, these results further confirm the potential of postsynthetic methods (including cation exchange) to obtain PCPs with novel or enhanced physical properties while maintaining unaltered their open-framework structures

Two-Dimensional 3d–4f Heterometallic Coordination Polymers: Syntheses, Crystal Structures, and Magnetic Properties of Six New Co(II)–Ln(III) Compounds

Six new heterometallic cobalt­(II)-lanthanide­(III) complexes of formulas [Ln­(bta)­(H₂O)₂]₂[Co­(H₂O)₆]·10H₂O [Ln = Nd­(III) (<b>1</b>) and Eu­(III) (<b>2</b>)] and [Ln₂Co­(bta)₂(H₂O)₈]_<i>n</i>·6<i>n</i>H₂O [Ln = Eu­(III) (<b>3</b>), Sm­(III) (<b>4</b>), Gd­(III) (<b>5</b>), and Tb­(III) (<b>6</b>)] (H₄bta = 1,2,4,5-benzenetretracaboxylic acid) have been synthesized and characterized via single-crystal X-ray diffraction. <b>1</b> and <b>2</b> are isostructural compounds with a structure composed of anionic layers of [Ln­(bta)­(H₂O)₂]_<i>n</i>^<i>n</i>– sandwiching mononuclear [Co­(H₂O)₆]²⁺ cations plus crystallization water molecules, which are interlinked by electrostatic forces and hydrogen bonds, leading to a supramolecular three-dimensional network. <b>3</b>–<b>6</b> are also isostructural compounds, and their structure consists of neutral layers of formula [Ln₂Co­(bta)₂(H₂O)₈]_<i>n</i> and crystallization water molecules, which are connected through hydrogen bonds to afford a supramolecular three-dimensional network. Heterometallic chains formed by the regular alternation of two nine-coordinate lanthanide­(III) polyhedra [Ln­(III)­O₉] and one compressed cobalt­(II) octahedron [Co­(II)­O₆] along the crystallographic <i>c</i>-axis are cross-linked by bta ligands within each layer of <b>3</b>–<b>6</b>. Magnetic susceptibility measurements on polycrystalline samples for <b>3</b>–<b>6</b> have been carried out in the temperature range of 2.0–300 K. The magnetic behavior of these types of Ln­(III)–Co­(II) complexes, which have been modeled by using matrix dagonalization techniques, reveals the lack of magnetic coupling for <b>3</b> and <b>4</b>, and the occurrence of weak antiferromagnetic interactions within the Gd­(III)−Gd­(III) (<b>5</b>) and Tb­(III)−Tb­(III) (<b>6</b>) dinuclear units through the exchange pathway provided by the double oxo­(carboxylate) and double syn–syn carboxylate bridges

Two-Dimensional 3d–4f Heterometallic Coordination Polymers: Syntheses, Crystal Structures, and Magnetic Properties of Six New Co(II)–Ln(III) Compounds

Six new heterometallic cobalt­(II)-lanthanide­(III) complexes of formulas [Ln­(bta)­(H₂O)₂]₂[Co­(H₂O)₆]·10H₂O [Ln = Nd­(III) (<b>1</b>) and Eu­(III) (<b>2</b>)] and [Ln₂Co­(bta)₂(H₂O)₈]_<i>n</i>·6<i>n</i>H₂O [Ln = Eu­(III) (<b>3</b>), Sm­(III) (<b>4</b>), Gd­(III) (<b>5</b>), and Tb­(III) (<b>6</b>)] (H₄bta = 1,2,4,5-benzenetretracaboxylic acid) have been synthesized and characterized via single-crystal X-ray diffraction. <b>1</b> and <b>2</b> are isostructural compounds with a structure composed of anionic layers of [Ln­(bta)­(H₂O)₂]_<i>n</i>^<i>n</i>– sandwiching mononuclear [Co­(H₂O)₆]²⁺ cations plus crystallization water molecules, which are interlinked by electrostatic forces and hydrogen bonds, leading to a supramolecular three-dimensional network. <b>3</b>–<b>6</b> are also isostructural compounds, and their structure consists of neutral layers of formula [Ln₂Co­(bta)₂(H₂O)₈]_<i>n</i> and crystallization water molecules, which are connected through hydrogen bonds to afford a supramolecular three-dimensional network. Heterometallic chains formed by the regular alternation of two nine-coordinate lanthanide­(III) polyhedra [Ln­(III)­O₉] and one compressed cobalt­(II) octahedron [Co­(II)­O₆] along the crystallographic <i>c</i>-axis are cross-linked by bta ligands within each layer of <b>3</b>–<b>6</b>. Magnetic susceptibility measurements on polycrystalline samples for <b>3</b>–<b>6</b> have been carried out in the temperature range of 2.0–300 K. The magnetic behavior of these types of Ln­(III)–Co­(II) complexes, which have been modeled by using matrix dagonalization techniques, reveals the lack of magnetic coupling for <b>3</b> and <b>4</b>, and the occurrence of weak antiferromagnetic interactions within the Gd­(III)−Gd­(III) (<b>5</b>) and Tb­(III)−Tb­(III) (<b>6</b>) dinuclear units through the exchange pathway provided by the double oxo­(carboxylate) and double syn–syn carboxylate bridges

Cation Exchange in Dynamic 3D Porous Magnets: Improvement of the Physical Properties

We report two novel three-dimensional porous coordination polymers (PCPs) of formulas Li₄{Mn₄[Cu₂(Me₃mpba)₂]₃}·68H₂O (<b>2</b>) and K₄{Mn₄[Cu₂(Me₃mpba)₂]₃}·69H₂O (<b>3</b>) obtainedvia alkali cation exchange in a single-crystal to single-crystal processfrom the earlier reported anionic manganese­(II)–copper­(II) PCP of formula Na₄{Mn₄[Cu₂(Me₃mpba)₂]₃}·60H₂O (<b>1</b>) [Me₃mpba^4– = <i>N,N</i>′-2,4,6-trimethyl-1,3-phenylenebis­(oxamate)]. This postsynthetic process succeeds where the direct synthesis in solution from the corresponding building blocks fails and affords significantly more robust PCPs with enhanced magnetic properties [long-range 3D magnetic ordering temperatures for the dehydrated phases (<b>1</b>′–<b>3</b>′) of 2.0 (<b>1</b>′), 12.0 (<b>2</b>′), and 20.0 K (<b>3</b>′)]. Changes in the adsorptive properties upon postsynthetic exchange suggest that the nature, electrostatic properties, mobility, and location of the cations within the framework are crucial for the enhanced structural stability. Overall, these results further confirm the potential of postsynthetic methods (including cation exchange) to obtain PCPs with novel or enhanced physical properties while maintaining unaltered their open-framework structures

Synthesis, crystal structure and magnetic characterization of a series of CuII-LnIII heterometallic [Ln = La, Ce, Pr, Nd and Sm) metal-organic compounds with an unusual single crystal to single crystal phase transition

The synthesis and structural characterization of five Cu(II)-Ln(III) heteronuclear metal-organic frameworks of formula {[Ln4Cu 4(H2O)26(bta)5]·mH 2O}n and {[Ln4Cu4(H 2O)24(bta)5]·pH2O} n [Ln = LaIII (1A/1B), CeIII (2A/2B), Pr III (3A/3B), NdIII (4A/4B) and SmIII (5A/5B) with m/p = 20 (1A)/16 (1B), 18 (2A)/16 (2B), 14 (3A)/16 (3B), 22 (4A)/16 (4B) and 21 (5A)/14 (5B); H4bta =1,2,4,5-benzenetetracarboxylic acid (1-5)] have been performed. These compounds present a single-crystal to single-crystal phase transition from expanded A phases toward the B shrinking networks, which is triggered only in the presence of a dry environment. This phase transition is accompanied by a compression of the crystallographic b-axis in the range 2.4 to 2.8 Å with the consequent decrease of the unit cell volume from 9.5% to 12%. The isomorphous crystal structures of 1A-5A can be described as two crystallographically independent [Cu(II)-Ln(III)] heterometallic dinuclear units which are connected through two crystallographically independent bta4- ligands in the ac-plane, leading to 4,4-rectangular grids. These layers are connected along the crystallographic b-axis, through a pillaring bta4- group. The phase transition implies a change of the coordination mode of the bta4- pillar from bis-monodentate (1A-5A) to tetrakis-monodentate (1B-5B). Magnetic susceptibility measurements of polycrystalline samples of 1A-5A in the temperature range 2.0-300 K have in common the decrease of the χMT product with T which in the case of 1A is due to weak antiferromagnetic interactions between the copper(II) ions through the bta 4- skeleton, the LaIII cation being diamagnetic [J = -3.5 cm-1 with the Hamiltonian defined H = -JSCu1·S Cu2]. For the 2A-5A compounds, the additional exchange interaction between CuII and the paramagnetic LnIII is masked by the crystal field effects (which partially removes the 2J + 1 degeneracy of the 2S+1LJ free-ion ground state in zero magnetic field) (2A-5A) and the thermal population of excited free-ion states (5A). © 2013 American Chemical Society.Funding for this work was partially provided Ministerio Español de Economia y Competitividad through Projects MAT2010-16981, MAT2011-27233-C0-02, DPI2010-21103-C04-03, CTQ2010-15364 and “Factoría de Cristalización” (Consolider- Ingenio2010, CSD2006-00015), the Gobierno de Canarias through projects PIL2070901 and structuring NANOMAC and the Generalitat Valenciana (PROMETEO2009/108 and ISIC/2012/002). P.D-G. and J.P. also thank Ministerio Español de Economia y Competitividad through FPI program and the NANOMAC project for predoctoral and postdoctoral contracts, respectively.Peer Reviewe