High-pressure studies of palladium and platinum thioether macrocyclic dihalide complexes

The mononuclear macrocyclic PdIIcomplexcis-[PdCl2([9]aneS3)] ([9]aneS3= 1,4,7-trithiacyclo-nonane) converts at 44 kbar into an intensely coloured chain polymer exhibiting distorted octahedral coordination at the metal centre and an unprecedented [1233] conformation for the thioether ligand. The evolution of an intramolecular axial sulfur–metal interaction and an intermolecular equatorial sulfur–metal interaction is central to these changes. High-pressure crystallographic experiments have also been undertaken on the related complexes [PtCl2([9]aneS3)], [PdBr2([9]aneS3)], [PtBr2([9]aneS3)], [PdI2([9]aneS3)] and [PtI2([9]aneS3)] in order to establish the effects of changing the halide ligands and the metal centre on the behaviour of these complexes under pressure. While all complexes undergo contraction of the various interaction distances with increasing pressure, only [PdCl2([9]aneS3)] undergoes a phase change. Pressure-induced I...I interactions were observed for [PdI2([9]aneS3)] and [PtI2([9]aneS3)] at 19 kbar, but the corresponding Br...Br interactions in [PdBr2([9]aneS3)] and [PtBr2([9]aneS3)] only become significant at much higher pressure (58 kbar). Accompanying density functional theory (DFT) calculations have yielded interaction energies and bond orders for the sulfur–metal interactions.

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High-Pressure Adsorption of Supercritical Gases on Activated Carbons: An Improved Approach Based on the Density Functional Theory and the Bender Equation of State

Langmuir ◽

10.1021/la030119w ◽

2003 ◽

Vol 19 (20) ◽

pp. 8349-8357 ◽

Cited By ~ 27

Author(s):

E. A. Ustinov ◽

D. D. Do

Keyword(s):

Density Functional Theory ◽

High Pressure ◽

Equation Of State ◽

Density Functional ◽

Activated Carbons ◽

Functional Theory ◽

The Density Functional Theory ◽

High Pressure Adsorption

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(Hexafluorosilicato-κ2F,F′)bis(1,10-phenanthroline-κ2N,N′)zinc(II) methanol monosolvate

Acta Crystallographica Section C Crystal Structure Communications ◽

10.1107/s0108270113023007 ◽

2013 ◽

Vol 69 (10) ◽

pp. 1112-1115 ◽

Cited By ~ 1

Author(s):

Rüdiger W. Seidel ◽

Christina Dietz ◽

Jürgen Breidung ◽

Richard Goddard ◽

Iris M. Oppel

Keyword(s):

Density Functional ◽

Crystal Packing ◽

Point Group ◽

Solvent Molecule ◽

Title Complex ◽

Group Symmetry ◽

Density Functional Theory Study ◽

Functional Theory ◽

Distorted Octahedral Coordination ◽

Distorted Octahedral

The title compound, [Zn(SiF6)(C12H8N2)2]·CH3OH, contains a neutral heteroleptic tris-chelate ZnIIcomplex,viz.[Zn(SiF6)(phen)2] (phen is 1,10-phenanthroline), exhibiting approximate molecularC2point-group symmetry. The ZnIIcation adopts a severely distorted octahedral coordination. As far as can be ascertained, the title complex represents the first structurally characterized example of a ZnIIcomplex bearing a bidentate-bound hexafluorosilicate ligand. A density functional theory study of the isolated [Zn(SiF6)(phen)2] complex was undertaken to reveal the influence of crystal packing on the molecular structure of the complex. In the crystal structure, the methanol solvent molecule forms a hydrogen bond to one F atom of the hexafluorosilicate ligand. The hydrogen-bonded assemblies so formed are tightly packed in the crystal, as indicated by a high packing coefficient (74.1%).

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STRUCTURAL TRANSITIONS OF BiI3 UNDER PRESSURE

Modern Physics Letters B ◽

10.1142/s021798491250217x ◽

2012 ◽

Vol 26 (32) ◽

pp. 1250217

Author(s):

XIAO-XIAO SUN ◽

ZHI-RU REN ◽

DAO-GUANG WANG

Keyword(s):

First Principles ◽

Density Functional ◽

Structural Transition ◽

High Pressures ◽

Functional Theory ◽

High Pressure Studies ◽

Volume Collapse ◽

Pseudopotential Calculations ◽

Structural And Electronic Properties ◽

Pnma Phase

High pressure studies of BiI 3 at 0 K are performed using first-principles pseudopotential calculations within the framework of density functional theory. The calculations indicate that BiI 3 undergoes a structural transition from rhombohedral R-3 phase to monoclinic P2 1/c phase at 7 GPa which is accompanied by a 5.8% volume collapse. In addition, we find that P2 1/c phase prevails about 60 GPa range and transforms to cubic Fm-3m phase at 68 GPa, and finally takes the orthorhombic Pnma phase at high pressures up to 133 GPa. The structural and electronic properties of four competitive structures are also calculated. The analysis of density of states reveals that BiI 3 has semiconductor-metal transition at about 61 GPa, which also demonstrates the metallic nature of both Fm-3m and Pnma phases.

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Compression Behavior and Vibrational Properties of New Energetic Material LLM-105 Analyzed Using the Dispersion-Corrected Density Functional Theory

Molecules ◽

10.3390/molecules26226831 ◽

2021 ◽

Vol 26 (22) ◽

pp. 6831

Author(s):

Tianming Li ◽

Junyu Fan ◽

Zhuoran Wang ◽

Hanhan Qi ◽

Yan Su ◽

...

Keyword(s):

Density Functional Theory ◽

High Pressure ◽

Uniaxial Compression ◽

Density Functional ◽

Structural Parameters ◽

Energetic Material ◽

Structure Stability ◽

Vibrational Properties ◽

Detailed Knowledge ◽

Functional Theory

The 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105) is a newly energetic material with an excellent performance and low sensitivity and has attracted considerable attention. On the basis of the dispersion-corrected density functional theory (DFT-D), the high-pressure responses of vibrational properties, in conjunction with structural properties, are used to understand its intermolecular interactions and anisotropic properties under hydrostatic and uniaxial compressions. At ambient and pressure conditions, the DFT-D scheme could reasonably describe the structural parameters of LLM-105. The hydrogen bond network, resembling a parallelogram shape, links two adjacent molecules and contributes to the structure stability under hydrostatic compression. The anisotropy of LLM-105 is pronounced, especially for Raman spectra under uniaxial compression. Specifically, the red-shifts of modes are obtained for [100] and [010] compressions, which are caused by the pressure-induced enhance of the strength of the hydrogen bonds. Importantly, coupling modes and discontinuous Raman shifts are observed along [010] and [001] compressions, which are related to the intramolecular vibrational redistribution and possible structural transformations under uniaxial compressions. Overall, the detailed knowledge of the high-pressure responses of LLM-105 is established from the atomistic level. Uniaxial compression responses provide useful insights for realistic shock conditions.

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Structural, Non-Covalent Interaction, and Natural Bond Orbital Studies on Bromido-Tricarbonyl Rhenium(I) Complexes Bearing Alkyl-Substituted 1,4-Diazabutadiene (DAB) Ligands

Crystals ◽

10.3390/cryst10040267 ◽

2020 ◽

Vol 10 (4) ◽

pp. 267 ◽

Cited By ~ 2

Author(s):

Reza Kia ◽

Azadeh Kalaghchi

Keyword(s):

Density Functional ◽

Natural Bond Orbital ◽

Carbonyl Groups ◽

X Ray Diffraction ◽

Functional Theory ◽

Covalent Interaction ◽

Distorted Octahedral ◽

Elemental Analyses ◽

Ft Ir ◽

Solid State Structures

The synthesis, characterization, structural and computational studies of Re(I) tricarbonyl bromo complexes bearing alkyl-substituted 1,4-diazabutadiene ligands, [Re(CO)3(1,4-DAB)Br], where 1,4-DAB = N,N-bis(2,4-dimethylbenzene)-1,4-diazabutadiene, 2,4-Me2DAB (1); N,N-bis(2,4-dimethylbenzene)-2,3-dimethyl-1,4-diazabutadiene, 2,4-Me2DABMe (2); N,N-bis(2,4,6-trimethylbenzene)-1,4-diazabutadiene, 2,4,6-Me3DAB (3); and N,N-bis(2,6-diisopropylbenzene)-1,4-diazabutadiene, 2,6-ipr2DAB (4) are reported. The complexes were characterized by different spectroscopic methods such as FT-IR, 1H-NMR, 13C-NMR, and elemental analyses and their solid-state structures were confirmed by X-ray diffraction. In each complex, the Re(I) centre shows a distorted octahedral shape with a facial geometry of carbonyl groups. The gas phase geometry of the complexes was identified by density functional theory. Interesting intermolecular n…π* interactions of complexes 1 and 3 were investigated by non-covalent interaction index (NCI), and natural bond orbital (NBO) analyses. The intramolecular n…σ*, σ…π*, π…σ* interactions were also studied in complexes 3 and 4.

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Hydrogen bonding and π–π interactions in the cocrystal salt [Fe(bpe)2(H2O)4](TCEP)2·2(bpe) [bpe is trans-1,2-bis(pyridin-4-yl)ethene and TCEP is 1,1,3,3-tetracyano-2-ethoxypropenide]

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229619002444 ◽

2019 ◽

Vol 75 (3) ◽

pp. 348-353

Author(s):

Abderrezak Addala ◽

David K. Geiger ◽

Zouaoui Setifi ◽

Fatima Setifi

Keyword(s):

Hydrogen Bonding ◽

Density Functional ◽

Complex Cation ◽

Electron Delocalization ◽

Coordination Geometry ◽

Inversion Center ◽

Functional Theory ◽

Π Interactions ◽

Distorted Octahedral Coordination Geometry ◽

Distorted Octahedral

The cocrystal salt tetraaquabis[trans-1,2-bis(pyridin-4-yl)ethene-κN]iron(II) bis(1,1,3,3-tetracyano-2-ethoxypropenide)–trans-1,2-bis(pyridin-4-yl)ethene (1/2), [Fe(C12H10N2)2(H2O)4](C9H5N4O)2·2C12H10N2, is a rare example of a mononuclear FeII compound with trans-1,2-bis(pyridin-4-yl)ethane (bpe) ligands. The complex cation resides on a crystallographically imposed inversion center and exhibits a tetragonally distorted octahedral coordination geometry. Both the symmetry-independent bpe ligand and the cocrystallized bpe molecule are essentially planar. The 1,1,3,3-tetracyano-2-ethoxypropenide counter-ion is nonplanar and the bond lengths are consistant with significant electron delocalization. The extended structure exhibits an extensive O—H...N hydrogen-bonding network with layers of complex cations joined by the cocrystallized bpe. Both the coordinated and the cocrystallized bpe are involved in π–π interactions. Hirshfeld and fingerprint plots reveal the important intermolecular interactions. Density functional theory was used to estimate the strengths of the hydrogen-bonding and π–π interactions, and suggest that the O—H...N hydrogen bonds enhance the strength of the π-interactions by increasing the polarization of the pyridine rings.

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