Dispersion analysis of a reconfigurable unit cell in a one dimensional periodic architecture

2012 ◽  
Author(s):  
D. N. P Thalakotuna ◽  
L. Matekovits ◽  
Karu P. Esselle ◽  
Stuart Hay ◽  
Michael Heimlich
Keyword(s):  
Dispersion Analysis ◽  
Unit Cell ◽  
One Dimensional

One-dimensional DABCO hydrogen-bonding chain in a hexagonal channel of magnetic [Ni(dmit)2]

2020 ◽  
Vol 49 (46) ◽  
pp. 16772-16777
Author(s):  
Simin Li ◽  
Kiyonori Takahashi ◽  
Ichiro Hisaki ◽  
Kenta Kokado ◽  
Takayoshi Nakamura
Keyword(s):  
Hydrogen Bonding ◽  
Unit Cell ◽  
One Dimensional

(HDABCO+)9(DABCO)[Ni(dmit)2]9·6CH3CN had a hexapetal flower-like pattern of [Ni(dmit)2]−. The [Ni(dmit)2]− hexamers formed trimer units and stacked one-dimensionally including DABCO-CH3CN chain at the centre more than 150 Å long per unit cell.

A STUDY OF HIGHER-ORDER DISCONTINUOUS GALERKIN AND QUADRATIC LEAST-SQUARES STABILIZED FINITE ELEMENT COMPUTATIONS FOR ACOUSTICS

2006 ◽  
Vol 14 (01) ◽  
pp. 1-19 ◽  
Author(s):  
ISAAC HARARI ◽  
RADEK TEZAUR ◽  
CHARBEL FARHAT
Keyword(s):  
Least Squares ◽  
Discontinuous Galerkin ◽  
Large Scale ◽  
Dispersion Analysis ◽  
Stability Parameter ◽  
New Approach ◽  
One Dimensional ◽  
Stabilized Finite Element ◽  
Quadratic Interpolation ◽  
The Stability

One-dimensional analyses provide novel definitions of the Galerkin/least-squares stability parameter for quadratic interpolation. A new approach to the dispersion analysis of the Lagrange multiplier approximation in discontinuous Galerkin methods is presented. A series of computations comparing the performance of [Formula: see text] Galerkin and GLS methods with Q-8-2 DGM on large-scale problems shows superior DGM results on analogous meshes, both structured and unstructured. The degradation of the [Formula: see text] GLS stabilization on unstructured meshes may be a consequence of inadequate one-dimensional analysis used to derive the stability parameter.

Structure and Properties of Ultrathin Ge-Si Superlattices

1986 ◽  
Vol 67 ◽  
Author(s):  
J. Bevk ◽  
J. P. Mannaerts ◽  
L. C. Feldman ◽  
B. A. Davidson ◽  
W. P. Lowe ◽  
...  
Keyword(s):  
Optical Transition ◽  
Growth Direction ◽  
Unit Cell ◽  
Silicon Substrates ◽  
Optical Studies ◽  
One Dimensional ◽  
X Ray ◽  
Ordered Alloys ◽  
Diffraction Patterns ◽  
Highly Strained

ABSTRACTWe report the synthesis, structural characterization, and preliminary optical studies of ultrathin Ge-Si superlattices with individual sublayers smaller than the Si unit cell, grown by MBE on (001) silicon substrates. Structures are fabricated one monolayer at a time in a configuration GeGeSiSiGeGe..., resulting in either ordered alloys or complex cell superlattices. Rutherford backscattering and channeling experiments on these highly strained heterostructures indicate excellent crystallinity with tetragonal distortion as high as 3.5%. Electron diffraction patterns exhibit characteristic superlattice reflections indicative of one-dimensional layering with periodicity of four monolayers. X-ray scans along the growth direction at the (002) position in reciprocal space reveal a strong peak not observed in random GeSi alloys. This scattering is attributed indirectly to the GeSi ordered phase. The optical transition energies measured by Schottky barrier electroreflectance correspond to those expected from homogeneous alloys of the same composition; however, the width of optical transitions is less than 30 meV at room temperature, allowing a clear resolution of the splitting of the valence band by strain. Modification of the unit cell of the diamond lattice in this way should permit the design of materials with novel opto-electronic characteristics. Preliminary Raman and photoconductivity measurements are also reported.

Novel Polyanionic Topologies in Ag2VAsO6 and Ag6V2As2O13

2013 ◽  
Vol 68 (5-6) ◽  
pp. 611-615 ◽  
Author(s):  
Jürgen Nuss ◽  
Jan Curda ◽  
Martin Jansen
Keyword(s):  
Stainless Steel ◽  
Oxygen Pressure ◽  
Unit Cell ◽  
Two Dimensional ◽  
Unit Cell Parameters ◽  
Space Group ◽  
One Dimensional ◽  
Cell Parameters ◽  
High Oxygen Pressure ◽  
Silver Cations

Two new silver vanadate arsenates, Ag2VAsO6 and Ag6V2As2O13, have been prepared applying high oxygen pressure syntheses in stainless-steel autoclaves. Ag2VAsO6 crystallizes in space group P1 with unit cell parameters a=639.1(1), b=646.1(1), c=706.6(1) pm, α =116.105(3), ß =91.759(4), γ = 90:067(4)°, and Z =2 (R1 =0.058, 3935 independent reflections). The structure consists of AsO4 tetrahedra and VO6 octahedra which are linked to form two-dimensional 2¥[VAsO6]2- polyanions, separated by silver cations. Ag6V2As2O13 (C2=c, a=1895.9(2), b=536.40(6), c=1308:5(2) pm, ß =113:578(2)°, Z =4; R1 =0.030, 2571 independent reflections) displays as primary building units AsO4 tetrahedra and VO5 trigonal bipyramids which are condensed by sharing edges to one-dimensional 1¥[V2As2O13]6- ladder-like strands, set apart by the silver cations. These heteropolyanions are without precedent

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.

EPR of an exchange-coupled, hydrogen-bridged one-dimensional Cu(II) complex containing both octahedral and square pyramidal geometries in the same unit cell

2002 ◽  
Vol 100 (2) ◽  
pp. 287-295 ◽  
Author(s):  
CHANDRAN KARUNAKARAN ◽  
K. R. JUSTIN THOMAS ◽  
ARUNACHALAM SHUNMUGASUNDARAM ◽  
RAMACHANDRAN MURUGESAN
Keyword(s):  
Unit Cell ◽  
One Dimensional

scholarly journals N-Methyl-N-propyltryptamine (MPT)

IUCrData ◽  
2019 ◽  
Vol 4 (7) ◽  
Author(s):  
Andrew R. Chadeayne ◽  
James A. Golen ◽  
David R. Manke
Keyword(s):  
Hydrogen Bonds ◽  
Single Molecule ◽  
Title Compound ◽  
Unit Cell ◽  
Asymmetric Unit ◽  
One Dimensional ◽  
Ethyl Methyl

The title compound {systematic name: [2-(1H-indol-3-yl)ethyl](methyl)propylamine}, C14H20N2, has a single molecule in the asymmetric unit. The molecules in the unit cell are held together in infinite one-dimensional chains along [010] through N—H...N hydrogen bonds between indole H atoms and trialkylamine N atoms.

scholarly journals Second order homogenization of quasi-periodic structures

2018 ◽  
Vol 40 (4) ◽  
pp. 325-348
Author(s):  
Duc Trung Le ◽  
Jean-Jacques Marigo
Keyword(s):  
General Framework ◽  
Volume Fraction ◽  
Effective Properties ◽  
Periodic Structures ◽  
Expansion Method ◽  
Second Order ◽  
Unit Cell ◽  
One Dimensional ◽  
Minimization Problems ◽  
Asymptotic Expansion Method

The paper develops a general framework to derive the effective properties of quasi-periodic elastic medium. By using the asymptotic expansion method, the solution is expanded to the second order by solving a sequence of minimization problems. The effective stiffness tensors fields entering in the expression of the macroscopic energy are obtained by solving several families of microscopic problems posed on the unit cell and which bring into play only the microstructure. As an illustrative example, we consider an anti-plane elastic case of a heterogeneous cylinder made of a bi-layer laminate and submitted to the gravity. The unit cell being one-dimensional, all the associated elementary problems can be solved in a closed form and one shows that the effective energy of the medium expanded up to the second order depends not only on the strain gradient, but also on the gradient of the volume fraction \(\theta\) characterizing the repartition of the two materials in the laminate.

scholarly journals Orbital Effect on Carbyne Based Sensor

2021 ◽  
Author(s):  
Mohammad Taghi Ahmadi ◽  
Zahra Heidari ◽  
Meisam Rahmani ◽  
Mahan Ahmadi
Keyword(s):  
Band Structure ◽  
Band Gap ◽  
Density Of States ◽  
Nearest Neighbors ◽  
Unit Cell ◽  
Dimensional Structure ◽  
Electron Interaction ◽  
Structure Variation ◽  
One Dimensional ◽  
Orbital Effect

Abstract Carbyne material with sp-hybridized atoms has been considered as a one dimensional structure with unique properties which has been widely used in nanotechnology. In the presented work the effect of electron overlap energy in the form of electron interaction with in the unit cell and nearest neighbors is explored. In addition, the band structure variation under proposed interaction in one dimensional carbyne is investigated. The effect of overlap energy variation inside and outside the unit cell on the band gap is intended. Under proposed structure the effective mass and density of states parameters are explored. It is demonstrated that by increasing the interaction between s and p orbitals in the unit cell, the band gap increases. However, the band gap is decreased by increasing the interaction between s and p orbitals out the unit cell which can be sued as a sensing mechanism.

Sign in / Sign up

Export Citation Format

Share Document