Interactions of the SiHxCly Silicon Species with the Si4H9 Cluster

1992 ◽  
Vol 57 (2) ◽  
pp. 248-254
Author(s):  
Jaroslav Burda ◽  
Michal Bureš ◽  
Čestmír Černý
Keyword(s):  
Crystal Growth ◽  
Epitaxial Growth ◽  
Single Crystals ◽  
Surface Reaction ◽  
Reaction Conditions ◽  
Technological Method

The CNDO/2 method was applied to the investigation of the surface reaction occurring during the epitaxial growth of silicon single crystals. The aim of the work was to find silicon species from which the crystal growth is possible under the reaction conditions chosen to comply with the application of the CVD technological method. Calculations suggest that the SiH2, SiHCl and SiH3 species are feasible for the further growth.

Crystal Growth of Calcite Nano-Plate by Alternate Soaking Method, Using CDS Crystals

2010 ◽  
Vol 63 ◽  
pp. 425-430
Author(s):  
Koya Hayashi ◽  
M. Tomohara ◽  
K. Fujino ◽  
Genta Sakane ◽  
Y. Katayama
Keyword(s):  
Crystal Growth ◽  
Single Crystal ◽  
Epitaxial Growth ◽  
Single Crystals ◽  
Growth Mechanism ◽  
Structure Data ◽  
Lattice Matching ◽  
Dodecyl Sulfate

Hetero-epitaxial growth of calcite crystals on calcium dodecyl sulfate (Ca(DS)2 = CDS) single crystals was studied by alternate soaking method. The calcite (006) oriented single crystals grow on the (001) surface of the CDS. The hetero-epitaxial growth mechanism is discussed by the lattice matching of the a-c planes of calcite and CDS according to the structure data of the CDS single crystal.

Dimensionally-Controlled Hydrothermal Tm3+-doped Oxidic Nanocrystals and Their Photoluminescence Properties

2010 ◽  
Vol 1247 ◽  
Author(s):  
Rocío Calderón-Villajos ◽  
Carlos Zaldo ◽  
Concepción Cascales
Keyword(s):  
Single Crystals ◽  
Fluorescence Lifetimes ◽  
Photoluminescence Properties ◽  
Reaction Conditions ◽  
Hydrothermal Processes ◽  
Bulk Single Crystals ◽  
Template Free ◽  
Reaction Media

AbstractControlled reaction conditions in simple, template-free hydrothermal processes yield Tm-Lu2O3 and Tm-GdVO4 nanocrystals with well-defined specific morphologies and sizes. In both oxide families, nanocrystals prepared at pH 7 reaction media exhibit photoluminescence in ∼1.95 μm similar to bulk single crystals. For the lowest Tm3+ concentration (0.2 % mol) in GdVO4 measured 3H4 and 3F4 fluorescence lifetimes τ are very near to τrad.

Crystal growth and scintillation properties of tube shape-controlled Ce-doped Y3Al5O12 single crystals grown by micro-pulling-down method

2020 ◽  
Vol 13 (12) ◽  
pp. 125503
Author(s):  
Atsushi Kotaki ◽  
Masao Yoshino ◽  
Yuui Yokota ◽  
Takashi Hanada ◽  
Akihiro Yamaji ◽  
...  
Keyword(s):  
Crystal Growth ◽  
Single Crystals ◽  
Tube Shape ◽  
Shape Controlled

A polycentric growth model of gallium arsenide epitaxial layers from the gas phase with simultaneous diffusion, adsorption and chemical reaction

1988 ◽  
Vol 53 (12) ◽  
pp. 2995-3013
Author(s):  
Emerich Erdös ◽  
Jindřich Leitner ◽  
Petr Voňka ◽  
Josef Stejskal ◽  
Přemysl Klíma
Keyword(s):  
Growth Rate ◽  
Gallium Arsenide ◽  
Epitaxial Growth ◽  
Gas Phase ◽  
Surface Reaction ◽  
Quantitative Description ◽  
The Other ◽  
Rate Equations ◽  
Impact Interaction ◽  
Partial Pressures

For a quantitative description of the epitaxial growth rate of gallium arsenide, two models are proposed including two rate controlling steps, namely the diffusion of components in the gas phase and the surface reaction. In the models considered, the surface reaction involves a reaction triple - or quadruple centre. In both models three mechanisms are considered which differ one from the other by different adsorption - and impact interaction of reacting particles. In every of the six cases, the pertinent rate equations were derived, and the models have been confronted with the experimentally found dependences of the growth rate on partial pressures of components in the feed. The results are discussed with regard to the plausibility of individual mechanisms and of both models, and also with respect to their applicability and the direction of further investigations.

scholarly journals Single Crystal Growth and Physical Properties of Pyroxene CoGeO3

Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 378
Author(s):  
Li Zhao ◽  
Zhiwei Hu ◽  
Hanjie Guo ◽  
Christoph Geibel ◽  
Hong-Ji Lin ◽  
...  
Keyword(s):  
High Pressure ◽  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Crystal Growth ◽  
Physical Properties ◽  
Single Crystal ◽  
Single Crystals ◽  
Magnetic Moments ◽  
Single Crystal Growth ◽  
The Impact

We report on the synthesis and physical properties of cm-sized CoGeO3 single crystals grown in a high pressure mirror furnace at pressures of 80 bar. Direction dependent magnetic susceptibility measurements on our single crystals reveal highly anisotropic magnetic properties that we attribute to the impact of strong single ion anisotropy appearing in this system with TN∼33.5 K. Furthermore, we observe effective magnetic moments that are exceeding the spin only values of the Co ions, which reveals the presence of sizable orbital moments in CoGeO3.

Trends in Rare Earth Thiophosphate Syntheses: Rb3Ln(PS4)2 (Ln = La, Pr, Ce), Rb3-xNaxLn(PS4)2 (Ln = Pr, Ce; x = 0.50, 0.55), and RbEuPS4 Obtained by Molten Flux Crystal Growth

CrystEngComm ◽  
2021 ◽  
Author(s):  
Logan S Breton ◽  
Mark D. Smith ◽  
Hans-Conrad Zur Loye
Keyword(s):  
Rare Earth ◽  
Crystal Growth ◽  
Single Crystals ◽  
Molten Flux

Single crystals of new rubidium rare earth thiophosphates with the formulas Rb3Ln(PS4)2 (Ln = La, Pr, Ce), Rb3-xNaxLn(PS4)2 (Ln = Pr, Ce; x = 0.50, 0.55), and RbEuPS4 were crystallized...

scholarly journals Numerical Analysis of Difficulties of Growing Large-Size Bulk β-Ga2O3 Single Crystals with the Czochralski Method

Crystals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 25
Author(s):  
Xia Tang ◽  
Botao Liu ◽  
Yue Yu ◽  
Sheng Liu ◽  
Bing Gao
Keyword(s):  
Crystal Growth ◽  
Single Crystals ◽  
Czochralski Method ◽  
Liquid Interface ◽  
Spiral Growth ◽  
Growth Time ◽  
Large Size ◽  
Crystal Diameter ◽  
Solid Liquid Interface ◽  
Solid Liquid

The difficulties in growing large-size bulk β-Ga2O3 single crystals with the Czochralski method were numerically analyzed. The flow and temperature fields for crystals that were four and six inches in diameter were studied. When the crystal diameter is large and the crucible space becomes small, the flow field near the crystal edge becomes poorly controlled, which results in an unreasonable temperature field, which makes the interface velocity very sensitive to the phase boundary shape. The effect of seed rotation with increasing crystal diameter was also studied. With the increase in crystal diameter, the effect of seed rotation causes more uneven temperature distribution. The difficulty of growing large-size bulk β-Ga2O3 single crystals with the Czochralski method is caused by spiral growth. By using dynamic mesh technology to update the crystal growth interface, the calculation results show that the solid–liquid interface of the four-inch crystal is slightly convex and the center is slightly concave. With the increase of crystal growth time, the symmetry of cylindrical crystal will be broken, which will lead to spiral growth. The numerical results of the six-inch crystal show that the whole solid–liquid interface is concave and unstable, which is not conducive to crystal growth.

scholarly journals Templated interfacial synthesis of metal-organic framework (MOF) nano- and micro-structures with precisely controlled shapes and sizes

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Lingyao Meng ◽  
Binyu Yu ◽  
Yang Qin
Keyword(s):  
Crystal Growth ◽  
Metal Organic Framework ◽  
Reaction Conditions ◽  
Zeolitic Imidazolate Framework ◽  
Crystallographic Preferred Orientation ◽  
Metal Organic ◽  
Interfacial Synthesis ◽  
Oil Water ◽  
Synthesis Methodology ◽  
Micro Structures

AbstractMetal-organic frameworks (MOF) are an emerging class of microporous materials with promising applications. MOF nanocrystals, and their assembled super-structures, can display unique properties and reactivities when compared with their bulk analogues. MOF nanostructures of 0-D, 2-D, and 3-D dimensions can be routinely obtained by controlling reaction conditions and ligand additives, while formation of 1-D MOF nanocrystals (nanowires and nanorods) and super-structures has been relatively rare. We report here a facile templated interfacial synthesis methodology for the preparation of a series of 1-D MOF nano- and micro-structures with precisely controlled shapes and sizes. Specifically, by applying track-etched polycarbonate (PCTE) membranes as the templates and at the oil/water interface, we rapidly and reproducibly synthesize zeolitic imidazolate framework-8 (ZIF-8) and ZIF-67 nano- and micro structures of sizes ranging from 10 nm to 20 μm. We also identify a size confinement effect on MOF crystal growth, which leads to single crystals under the most restricted conditions and inter-grown polycrystals at larger template pore sizes, as well as surface directing effects that influence the crystallographic preferred orientation. Our findings provide a potentially generalizable method for controlling the size, morphology, and crystal orientations of MOF nanomaterials, as well as offering fundamental understanding into MOF crystal growth mechanisms.

Large-sized crystal growth and piezoelectric properties of the single crystals of LiNa5Mo9O30

CrystEngComm ◽  
2021 ◽  
Vol 23 (9) ◽  
pp. 1912-1917
Author(s):  
Xiaoli Du ◽  
Fuan Liu ◽  
Zeliang Gao ◽  
Xiaojie Guo ◽  
Xiangmei Wang ◽  
...  
Keyword(s):  
Dipole Moment ◽  
Crystal Growth ◽  
Single Crystals ◽  
Piezoelectric Properties ◽  
First Time ◽  
Octahedral Distortion

Single crystals of LiNa5Mo9O30 with seeds in the a-, b- and c-directions were successfully grown using the TSSG method. Full sets of dielectric, elastic and piezoelectric matrices of the crystal were determined first time. The octahedral distortion and dipole moment are calculated to explain the piezoelectric properties.

Sign in / Sign up

Export Citation Format

Share Document