Electron–phonon interaction in three-, two- and one-dimensional ternary mixed crystals

2016 ◽  
Vol 30 (15) ◽  
pp. 1650182
Author(s):  
Junhua Hou ◽  
Yunpeng Fan
Keyword(s):  
Cell Volume ◽  
Effective Mass ◽  
Unit Cell Volume ◽  
Three Dimensional ◽  
Unit Cell ◽  
Mixed Crystals ◽  
Phonon Interaction ◽  
One Dimensional ◽  
Electron Phonon Interaction ◽  
Self Trapping

The electron–phonon (e–p) interaction in three-dimensional (3D), two-dimensional (2D) and one-dimensional (1D) ternary mixed crystals is studied. The e–p interaction Hamiltonians including the unit cell volume variation in ternary mixed crystals are obtained by using the modified random-element-isodisplacement model and Born–Huang method. The polaronic self-trapping energy and renormalized effective mass of GaAs[Formula: see text]Sb[Formula: see text], GaP[Formula: see text]As[Formula: see text] and GaP[Formula: see text]Sb[Formula: see text] compounds are numerically calculated. It is confirmed theoretically that the nonlinear variation of the self-trapping energy and effective mass with the composition is essential and the unit cell volume effects cannot be neglected except the weak e–p coupling. The dimensional effect cannot also be ignored.

Electron–phonon interaction in quasi-1D ternary mixed crystals of polar semiconductors

2015 ◽  
Vol 29 (23) ◽  
pp. 1550130 ◽  
Author(s):  
Yunpeng Fan ◽  
Junhua Hou
Keyword(s):  
Cell Volume ◽  
Unit Cell Volume ◽  
Mixed Crystal ◽  
Random Element ◽  
Unit Cell ◽  
Mixed Crystals ◽  
Phonon Modes ◽  
Phonon Interaction ◽  
One Dimensional ◽  
Electron Phonon Interaction

The electron–optical-phonon interaction between an electron and two branches of LO-phonon modes in a quasi-one-dimensional ternary mixed crystal (TMC) of polar semiconductors is studied. The new electron–phonon interaction Hamiltonian including the unit-cell volume variation in TMCs is obtained by using the modified random element isodisplacement model and Born–Huang method. The energies of polaron are numerically calculated for several systems of III–V compounds. A group of III-nitride mixed crystals is also taken into numerical calculation in our theory. It is verified theoretically that the obvious nonlinearity of the polaronic energy and effective mass with the composition is essential and the unit-cell volume effects cannot be neglected except the very weak e–p coupling.

A three-dimensional anionic metal–dicyanamide network in poly[ethyltriphenylphosphonium [tri-μ2-dicyanamidato-cadmium(II)]]

2015 ◽  
Vol 71 (1) ◽  
pp. 65-68 ◽  
Author(s):  
Qiang Li
Keyword(s):  
Cell Volume ◽  
Title Compound ◽  
Unit Cell Volume ◽  
Three Dimensional ◽  
Unit Cell ◽  
Void Space ◽  
Compound C

The title compound, (C20H20P)[Cd(C2N3)3], consists of ethyltriphenylphosphonium (EtPh3P+) cations filling voids in a three-dimensional anionic cadmium dicyanamide network. In the structure, each CdIIatom is connected to six neighbouring CdIIatoms through six separate dicyanamide ligands, forming cube-shaped cages. The three-dimensional anionic network encloses a solvent-accessible void space of 1851 Å3, amounting to 69.3% of the unit-cell volume. Each cage accommodates only one EtPh3P+cation.

A Two-Dimensional Coordination Polymer Formed from Cobalt(II) and an Extended Dipyridyl Ligand

2020 ◽  
Vol 73 (6) ◽  
pp. 547 ◽  
Author(s):  
Hydar A. AL-Fayaad ◽  
Rashid G. Siddique ◽  
Kasun S. Athukorala Arachchige ◽  
Jack K. Clegg
Keyword(s):  
Coordination Polymer ◽  
Cell Volume ◽  
Crystal Structures ◽  
Unit Cell Volume ◽  
Suzuki Coupling ◽  
Unit Cell ◽  
Square Lattice ◽  
Two Dimensional ◽  
Cobalt Ions ◽  
One Dimensional

The synthesis of the extended dipyridyl ligand 4,4′-(2,5-dimethyl-1,4-phenylene)dipyridine (L) in an improved yield via the palladium catalysed Suzuki coupling of 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine (1) and 1,4-dibromo-2,5-dimethylbenzene (2) is reported along with its use to form a two-dimensional coordination polymer [Co2L2(OAc)4(H2O)2]n. The coordination polymer consists of one-dimensional chains of octahedral cobalt ions bridged by acetate ligands which are connected to form two dimensional sheets with square lattice (sql) topology via the dipyridyl ligands (L). The structure contains small voids totalling ~6.6% of the unit cell volume. The crystal structures 1, L, L·2H2O, and L·2HNO3 are also reported.

scholarly journals Ethyl α-L-sorboside

IUCrData ◽  
2020 ◽  
Vol 5 (12) ◽  
Author(s):  
Natsumi Nagayama ◽  
Norito Taniguchi ◽  
Mao Matsumoto ◽  
Kei Takeshita ◽  
Tomohiko Ishii
Keyword(s):  
Hydrogen Bonds ◽  
Cell Volume ◽  
Unit Cell Volume ◽  
Three Dimensional ◽  
Unit Cell ◽  
Rare Sugar ◽  
Dimensional Network

Ethyl L-sorboside, C8H16O6, was prepared from the rare sugar L-sorbose, C6H12O6, and crystallized. It was confirmed that ethyl L-sorboside formed α-pyranose with a 2 C 5 conformation. In the crystal, molecules are linked by O—H...O hydrogen bonds, forming a three-dimensional network. The unit-cell volume of the title ethyl α-L-sorboside is 940.63 Å3 (Z = 4), which is about 194.69 Å3 (26.1%) bigger than that of L-sorbose [745.94 Å3 (Z = 4)].

scholarly journals Single Crystal X-Ray Structural Investigation of Alluaudite Related Monophosphate Na2FeMn2(PO4)3

2010 ◽  
Vol 12 (3,4) ◽  
pp. 213
Author(s):  
Nezha Dridi ◽  
El Hassan Arbib ◽  
El Hassan Karni ◽  
Francesco Capitelli ◽  
Brahim Elouadi
Keyword(s):  
Single Crystal ◽  
Cell Volume ◽  
Unit Cell Volume ◽  
Structural Investigation ◽  
Three Dimensional ◽  
Structural Type ◽  
Unit Cell ◽  
X Ray Diffraction ◽  
X Ray ◽  
Dimensional Network

<p>The compound Na<sub>2</sub>FeMn<sub>2</sub>(PO<sub>4</sub>)<sub>3</sub> has been successfully isolated with the alluaudite structural type. Accurate single crystal X-Ray diffraction has allowed solving the structure with reliability factors of R<sub>1</sub> and Rw equal to 0.0322 and 0.0790 respectively. It was found that the symmetry is monoclinic with a space group of C2/c and lattice parameters: a = 12.180(2) Å, b = 12.660(2) Å, c = 6.500(2) Å, b = 114.528(3)(°), unit cell volume = 911.8(3) Å<sup>3</sup>, Z = 8 and d<sub>cal.</sub>=3.618 g.cm<sup>-3</sup>. Three-dimensional network is formed by the [MnO<sub>6</sub>] octahedra linked in pairs to form Mn-based octahedral dimers: ([Mn<sub>2</sub>O<sub>10</sub>]). Each dimer shares six vertices with six tetrahedra [P(2)O<sub>4</sub>] to form sheets within the plane (100). The latter are connected by tetrahedra [P(1)O<sub>4</sub>] delimiting cages and tunnels which house either Fe<sup>3+</sup> or Na<sup>+</sup> cations. Each [FeO<sub>6</sub>] octahedron is linked to two [Mn<sub>2</sub>O<sub>10</sub>] dimers belonging to two adjacent sheets to form mixed Fe-Mn chains of the type: - Fe<sup>3+</sup> - Mn<sup>2+</sup> - Mn<sup>2+</sup> - Fe<sup>3+</sup> - Mn<sup>2+</sup> - Mn<sup>2+</sup> - Fe<sup>3+</sup> - ..., running along the direction [101].<strong></strong></p>

scholarly journals Methyl α-L-sorboside monohydrate

IUCrData ◽  
2021 ◽  
Vol 6 (12) ◽  
Author(s):  
Mao Matsumoto ◽  
Natsumi Nagayama ◽  
Ryo Hirose ◽  
Kei Takeshita ◽  
Tomohiko Ishii
Keyword(s):  
Hydrogen Bonds ◽  
Water Molecule ◽  
Cell Volume ◽  
Title Compound ◽  
Unit Cell Volume ◽  
Three Dimensional ◽  
Unit Cell ◽  
Rare Sugar ◽  
Dimensional Network

Methyl L-sorboside monohydrate, C7H14O6·H2O, was prepared from the rare sugar L-sorbose, C6H12O6, and crystallized. It was confirmed that methyl L-sorboside formed α-pyranose with a 2 C 5 conformation and crystallized with one water molecule of crystallization. In the crystal, molecules are linked by O—H...O hydrogen bonds, forming a three-dimensional network. The unit-cell volume of the title compound, methyl L-sorboside monohydrate, is 481.13 (2) Å3 (Z = 2), which is about 108.16 Å3 (29.0%) greater than that of half the amount of the chemical α-L-sorbose [745.94 (2) Å3 (Z = 4)].

ELECTRON–PHONON INTERACTION IN WURTZITE AlxGa1-xN TERNARY CRYSTAL

2007 ◽  
Vol 21 (22) ◽  
pp. 3841-3850 ◽  
Author(s):  
SHU YI WEI ◽  
FANG ZHANG ◽  
WEI LI ◽  
ZU ZHAO ◽  
WEN DENG HUANG
Keyword(s):  
Unit Cell Volume ◽  
Unit Cell ◽  
Coupling Constants ◽  
Phonon Interaction ◽  
Electron Phonon Interaction ◽  
Effective Masses ◽  
Mode Behavior ◽  
Polaron Energy ◽  
The One ◽  
Ternary Nitride

Optical vibrations of the lattice and the electron-optical-phonon interaction in wurtzite ternary nitride-based crystals was studied using the pseudo-unit-cell approach. The Fröhlich coupling constants, polaron energy shifts and the effective masses of the polaron in the system were investigated using the perturbation method. It was found that the LO and TO phonons in wurtzite Al x Ga 1-x N exhibit the one-mode behavior. The effects of the unit-cell volume varying with the composition x of ternary nitride-based crystals were also investigated.

DIFFERENCE OF VARIATION OF UNIT CELL VOLUME V AND Tc WITH OXYGEN CONTENT IN YBa2Cu3O7−x AND LaBa2Cu3O7+x

1988 ◽  
Vol 02 (03n04) ◽  
pp. 641-650
Author(s):  
G.C. CHE ◽  
S.S. XIE ◽  
J.K. LIANG ◽  
K.S. LI ◽  
D.N. ZHENG ◽  
...  
Keyword(s):  
Cell Volume ◽  
Oxygen Content ◽  
Unit Cell Volume ◽  
Lattice Parameter ◽  
Unit Cell ◽  
Dimensional Chain ◽  
One Dimensional ◽  
The One

In YBa 2 Cu 3 O 7−x, the more the oxygen content is the higher is the Tc, the smaller is the lattice parameter c and the unit cell volume V. But in LaBa 2 Cu 3 O 7+x the less the oxygen content is, the higher is the Tc, the larger are c and V. These may be due to oxygen content being less than 7.0 in YBa 2 Cu 3 O 7−x and more than 7.0 in LaBa 2 Cu 3 O 7+x. These results give some informations regarding superconducting mechanism and show that the one-dimensional chain plays an important role.

Design of Organic Superconductors Based on Bedt-TTF

1992 ◽  
Vol 247 ◽  
Author(s):  
Gunzi Saito ◽  
Tokutaro Komatsu ◽  
Toshikazu Nakamura ◽  
Hideki Yamochi
Keyword(s):  
Cell Volume ◽  
Structural Properties ◽  
Unit Cell Volume ◽  
Structural Characteristics ◽  
Three Dimensional ◽  
Organic Superconductors ◽  
Unit Cell ◽  
Two Dimensional ◽  
Effective Volume ◽  
Anion Layer

ABSTRACTA close examination of the relation between Tc and structural characteristics of BEDT-TTF superconductors has revealed that there is a good correlation between the effective volume (VeffαVc-Vanion and Tc but no such correlation between the unit cell volume (Vc) and Tc. In order to increase Veff, it is favorable to use big but thin anion which can form a thin two-dimensional anion layer. Three-dimensional donor interactions are critical to have sizable Tc. According to the designing, two new superconductors; K-(BEDT-TTF)2CuCN[N(CN)2] (Tc=11.2K) and K'-(BEDT-TTF)2Cu2(CN)3 (Tc=3.8K), are prepared and their physical and structural properties are described. Their Tc's are discussed in terms of veff.

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