On the Structure of Carbon Films Deposited on Si(111) by Mass-Selected Low Energy C+ Beams

1989 ◽  
Vol 152 ◽  
Author(s):  
J. L. Robertson ◽  
X. G. Jiang ◽  
P. C. Chow ◽  
S. C. Moss ◽  
Y. Lifshitz ◽  
...  
Keyword(s):  
Raman Spectrum ◽  
Crystal Growth ◽  
Single Crystal ◽  
Single Crystals ◽  
Ion Beam ◽  
Diamond Films ◽  
Single Crystal Growth ◽  
Carbon Films ◽  
Low Energy ◽  
X Ray

ABSTRACTOur recent report of epitaxial single crystal growth of C+ ion-beam-deposited diamond films on (111) single crystals of silicon is shown to be incorrect. We briefly describe the circumstances leading to this revision (and to our earlier finding) and discuss the possible structure of these films based on preliminary synchrotron X-ray data and on the Raman spectrum.

Single Crystal Growth and Thermoelectric Properties of Ce5Cu19P12

1998 ◽  
Vol 545 ◽  
Author(s):  
K. J. Proctor ◽  
F. J. DiSalvo
Keyword(s):  
Electrical Resistivity ◽  
Crystal Growth ◽  
Single Crystal ◽  
Single Crystals ◽  
Room Temperature ◽  
Single Crystal Growth ◽  
Room Temperature Resistivity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Temperature Resistivity

AbstractSingle crystals of the known ternary cerium intermetallic Ce5Cu19P12were grown by Sn flux and I2transport methods. The long axis of the black hexagonal needles was confirmed to be the c-axis by single crystal X-ray diffraction. Electrical resistivity of both single crystals and a pressed pellet was measured from 4 - 300 K; the room temperature resistivity is about 400 μΩ-cm for the needle axis of the crystals and about 5 mΩ-cm for the pressed pellet. The thermopower of the pressed pellet was found to be 34 μV/K at room temperature.

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.

scholarly journals Growth of single crystals in the (Na1/2Bi1/2)TiO3–(Sr1–xCax)TiO3 system by solid state crystal growth

2021 ◽  
Author(s):  
Phan Gia Le ◽  
Huyen Tran Tran ◽  
Jong-Sook Lee ◽  
John G. Fisher ◽  
Hwang-Pill Kim ◽  
...  
Keyword(s):  
Crystal Growth ◽  
Solid State ◽  
Single Crystal ◽  
Single Crystals ◽  
Piezoelectric Properties ◽  
Single Crystal Growth ◽  
Crystal Growth Rate ◽  
Large Strains ◽  
Growth Technique ◽  
The Matrix

AbstractCeramics based on (Na1/2B1/2)TiO3 are promising candidates for actuator applications because of large strains generated by an electric field-induced phase transition. For example, the (1−x)(Na1/2Bi1/2)TiO3-xSrTiO3 system exhibits a morphotropic phase boundary at x = 0.2–0.3, leading to high values of inverse piezoelectric constant d*33, which can be further improved by the use of single crystals. In our previous work, single crystals of (Na1/2B1/2)TiO3-SrTiO3 and (Na1/2B1/2)TiO3-CaTiO3 were grown by the solid state crystal growth technique. Growth in the (Na1/2B1/2)TiO3-SrTiO3 system was sluggish whereas the (Na1/2B1/2)TiO3-CaTiO3 single crystals grew well. In the present work, 0.8(Na1/2Bi1/2)TiO3-0.2(Sr1−xCax)TiO3 single crystals (with x = 0.0, 0.1, 0.2, 0.3, 0.4) were produced by the solid state crystal growth technique in an attempt to improve crystal growth rate. The dependence of mean matrix grain size, single crystal growth distance, and electrical properties on the Ca concentration was investigated in detail. These investigations indicated that at x = 0.3 the matrix grain growth was suppressed and the driving force for single crystal growth was enhanced. Replacing Sr with Ca increased the shoulder temperature Ts and temperature of maximum relative permittivity Tmax, causing a decrease in inverse piezoelectric properties and a change from normal to incipient ferroelectric behavior.

Calcium Carbodiimide Compounds Revisited – Syntheses, Single Crystal Structure Determination and Vibrational Spectra of Ca11N6[CN2]2, Ca4N2[CN2] and Ca[CN2]

2008 ◽  
Vol 63 (5) ◽  
pp. 530-536 ◽  
Author(s):  
Olaf Reckeweg ◽  
Francis J. DiSalvo
Keyword(s):  
Crystal Structure ◽  
Raman Spectrum ◽  
Single Crystal ◽  
Single Crystals ◽  
Vibrational Spectra ◽  
Structure Determination ◽  
X Ray ◽  
Characteristic Features ◽  
Reported Data ◽  
Correct Data

Single crystals of Ca11N6[CN2]2 (dark red needles, tetragonal, P42/mnm (no. 136), a = 1456.22(5), and c = 361.86(2) pm, Z = 2), Ca4N2[CN2] (transparent yellow needles, orthorhombic, Pnma (no. 62), a = 1146.51(11), b = 358.33(4), and c = 1385.77(13) pm, Z = 4) and Ca[CN2] (transparent, colorless, triangular plates, rhombohedral, R3̅m (no. 166), a = 369.00(3), and c = 1477.5(3) pm, Z = 3) were obtained by the reaction of Na2[CN2], CaCl2 and Ca3N2 (if demanded by stoichiometry) in arc-welded Ta ampoules at temperatures between 1200 - 1400 K. Their crystal structures were re-determined by means of single crystal X-ray structure analyses. Additionally, the Raman spectra were recorded on these same single crystals, whereas the IR spectra were obtained with the KBr pellet technique. The title compounds exhibit characteristic features for carbodiimide units with D∞h symmetry (d(C-N) = 121.7 - 123.8 pm and ∡ (N-C-N) = 180°). The vibrational frequencies of these units are in the expected range (Ca11N6[CN2]2: νs = 1230, νs = 2008; δ = 673/645/624 cm−1; Ca4N2[CN2]: νs = 1230, νs = 1986; δ = 672/647 cm−1; Ca[CN2]: νs = 1274, νs = 2031, δ = 668 cm−1). The structural results are more precise than the previously reported data, and with the newly attained Raman spectrum of Ca11N6[CN2]2 we correct data reported earlier.

Flux-assisted single crystal growth and heteroepitaxy of perovskite-type mixed-metal borohydrides

CrystEngComm ◽  
2015 ◽  
Vol 17 (13) ◽  
pp. 2682-2689 ◽  
Author(s):  
Pascal Schouwink ◽  
Adrien Ramel ◽  
Enrico Giannini ◽  
Radovan Černý
Keyword(s):  
Crystal Growth ◽  
Single Crystal ◽  
Single Crystals ◽  
Single Crystal Growth ◽  
Mixed Metal ◽  
Perovskite Type

Single crystals of mixed-metal perovskite-type borohydride KCa(BH4)3 are prepared by using an easily generalized flux melting procedure based on eutectic borohydride systems.

scholarly journals Effect of Composition on the Growth of Single Crystals of (1−x)(Na1/2Bi1/2)TiO3-xSrTiO3 by Solid State Crystal Growth

Materials ◽  
2019 ◽  
Vol 12 (15) ◽  
pp. 2357 ◽  
Author(s):  
Le ◽  
Fisher ◽  
Moon
Keyword(s):  
Growth Rate ◽  
Crystal Growth ◽  
Solid State ◽  
Single Crystal ◽  
Single Crystals ◽  
Grain Growth ◽  
Ceramic Powder ◽  
Single Crystal Growth ◽  
Crystal Growth Rate ◽  
Mixed Control

The (1−x)(Na1/2Bi1/2)TiO3-xSrTiO3 (NBT-100xST) system is a possible lead-free candidate for actuator applications because of its excellent strain vs. electric field behaviour. Use of single crystals instead of polycrystalline ceramics may lead to further improvement in piezoelectric properties but work on single crystal growth in this system is limited. In particular, the effect of composition on single crystal growth has yet to be studied. In this work, single crystals of (NBT-100xST) with x = 0.00, 0.05, 0.10 and 0.20 were grown using the method of Solid State Crystal Growth. [001]-oriented SrTiO3 single crystal seeds were embedded in (NBT-100xST) ceramic powder, which was then pressed to form pellets and sintered at 1200 °C for 5 min–50 h. Single crystal growth rate, matrix grain growth rate and sample microstructure were examined using scanning and transmission electron microscopy. The results indicate that the highest single crystal growth rate was obtained at x = 0.20. The mixed control theory of grain growth is used to explain the single crystal and matrix grain growth behaviour.

Single Crystal Growth of YBa2Cu4O8 and Y2Ba4Cu7O15 Under High Oxygen Pressure

1991 ◽  
Vol 251 ◽  
Author(s):  
T. Miyatake ◽  
T. Takata ◽  
K. Yamaguchi ◽  
K. Takamuku ◽  
N. Koshizuka ◽  
...  
Keyword(s):  
Crystal Growth ◽  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Single Crystal ◽  
Single Crystals ◽  
Oxygen Pressure ◽  
Maximum Size ◽  
Single Crystal Growth ◽  
Mixed Gas ◽  
High Oxygen Pressure

ABSTRACTWe investigate the crystal growth of YBa2Cu4O8 (124) and Y2Ba4Cu7O15 (247) in Al2O3 crucibles at an oxygen partial pressure of 20MPa employing an O2- HIP apparatus in a mixed gas environment of Ar-20%O2. Various melts compositions, rich in Ba and Cu, are explored to optimize crystal growth of 124. Large 124 single crystals up to a size of 1×0.5×0.05mm3 are obtained from compositions with about 65˜67%CuO. 247 single crystals having a maximum size of 3×1.5×0.05mm3 are grown from the same composition of melts. 124 crystals exhibit superconductivity at 75K. 247 crystals show Tc of 20K.

SINGLE CRYSTAL GROWTH AND TEXTURING OF LEAD-BASED PIEZOELECTRIC CERAMICS VIA TEMPLATED GRAIN GROWTH PROCESS

2008 ◽  
Vol 01 (02) ◽  
pp. 127-132 ◽  
Author(s):  
THOMAS RICHTER ◽  
CARSTEN SCHUH ◽  
RALF MOOS ◽  
ENDER SUVACI
Keyword(s):  
Crystal Growth ◽  
Single Crystal ◽  
Single Crystals ◽  
Grain Growth ◽  
High Performance ◽  
Piezoelectric Materials ◽  
Secondary Recrystallization ◽  
Single Crystal Growth ◽  
Templated Grain Growth ◽  
Textured Ceramics

In the field of high-performance piezoelectric materials, PMN-PT single crystals and textured ceramics have been attracting increased research interest for several years. On the other hand, the growth of single crystals from melt for PZT-based compositions is impossible due to its incongruent melting behavior. In order to obtain the characteristics of pure single crystal PZT as closely as possible, the PZT must be textured by secondary recrystallization of introduced seeds in a fine-grained matrix. Zirconium was therefore added to a PMN-PT-ceramic with 32 mol% PT ( Pb ( Mg 1/3 Nb 2/3)0.68 Ti 0.32 O 3) in order to obtain a PMN-PZT-ceramic with 37 mol% PT and 21 mol% PZ ( Pb ( Mg 1/3 Nb 2/3)0.42( Ti 0.638 Zr 0.362)0.58 O 3). Initially, the growth mechanism of (001)-oriented BaTiO 3 (BT) single crystals in those matrices was investigated. The piezoelectric single crystals were produced via a process that starts with the hot pressing of a BT single crystal in cold isostatically pressed ceramics, followed by an additional sintering step in order to achieve a secondary recrystallization. The measured growth lengths in PMN-PT and PMN-PZT matrices were up to 140 μm and 65 μm, respectively. Having developed this understanding, both ceramics were textured via the templated grain growth (TGG) process by using (001)-oriented BT templates. Sintering of templated grain bodies resulted in template growth into the matrix to produce textured ceramics with Lotgering factors up to 0.99 for both compositions. In textured samples unipolar strain s33 was enhanced by a factor of up to 1.8 compared to randomly oriented ceramics. By contrast, BT single crystal growth in an alternative PZT matrix with NdMn doping was not successful. Hence, in the present work, growth experiments in this NdMn -doped PZT were first performed using PZT fibers of similar composition as seeds. Growth of the fiber diameter of up to 100 μm was observed in that matrix.

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