Lead Germanate Pb5Ge3O11 Crystal Growth

AbstractThe new thallide EuPdTl2, synthesized from the elements in a sealed tantalum tube in a highfrequency furnace, was investigated by X-ray diffraction on powders and single crystals: MgCuAl2 type, Cmcm, Z = 4, a = 446.6(1), b = 1076.7(2), c = 812.0(2) pm, wR2 = 0.0632, 336 F2 values, 16 variables. The structure can be considered as an orthorhombically distorted, palladium-filled variant of the binary Zintl phase EuTl2. The palladium and thallium atoms build up a three-dimensional [PdTl2] polyanion with significant Pd-Tl (286 - 287 pm) and Tl-Tl (323 - 329 pm) interactions. The europium atoms fill distorted hexagonal channels of the [PdTl2] polyanion. Susceptibility measurements show a magnetic moment of 7.46(5) μB/Eu atom, indicative of divalent europium. EuPdTl2 is a soft ferromagnet with a Curie temperature of TC = 12.5(5) K.

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Crystal growth, crystal structure, optical, electro-optic and electrostrictive properties of the orthorhombic tartrato-antimonate(III) nitrate KZn[Sb2{(+)-C4H2O6}2]NO3 · 5 H2O (“KZnSbTN”)

Zeitschrift für Kristallographie - Crystalline Materials ◽

10.1524/zkri.1994.209.1.14 ◽

1994 ◽

Vol 209 (1) ◽

Cited By ~ 1

Author(s):

L. Bohatý ◽

R. Fröhlich

Keyword(s):

Crystal Structure ◽

Crystal Growth ◽

Single Crystal ◽

Single Crystals ◽

Diffraction Data ◽

Title Compound ◽

X Ray Diffraction ◽

X Ray ◽

Electro Optic ◽

Electrostrictive Properties

AbstractKZnSbTN is an example from the large acentric double salt-like family of tartrato-antimonates. Its crystal structure was determined from single-crystal X-ray diffraction data (orthorhombic,Single crystals of the title compound of up to 4×4×6 cm

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Crucible Selection in AlN Bulk Crystal Growth

MRS Proceedings ◽

10.1557/proc-798-y2.9 ◽

2003 ◽

Vol 798 ◽

Cited By ~ 4

Author(s):

Rafael Dalmau ◽

Balaji Raghothamachar ◽

Michael Dudley ◽

Raoul Schlesser ◽

Zlatko Sitar

Keyword(s):

Mass Spectrometry ◽

Crystal Growth ◽

Single Crystals ◽

Secondary Ion Mass Spectrometry ◽

X Ray Diffraction ◽

Bulk Crystal Growth ◽

Growth Environment ◽

X Ray ◽

Spontaneous Nucleation ◽

Bulk Single Crystals

ABSTRACTGrowth of AlN bulk single crystals by sublimation of AlN powder was carried out in a resistively heated reactor at temperatures up to 2300°C. A variety of crucible materials, such as BN, W, Ta, Re, ZrO2, TaN, and TaC, were evaluated. Our studies have shown that the morphology of crystals grown by spontaneous nucleation strongly depends on the growth temperature and contamination in the reactor. Crucible selection had a profound effect on contamination in the crystal growth environment, thus influencing nucleation, coalescence, and crystal morphology. Spontaneously grown single crystals up to 15 mm in size were characterized by x-ray diffraction (XRD), x-ray topography (XRT), glow discharge mass spectrometry (GDMS), and secondary ion mass spectrometry (SIMS). Average dislocation densities were on the order of 103 cm−3, with extended areas virtually dislocation-free, while high-resolution XRD showed rocking curves as narrow as 7 arcsec.

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Single Crystal Growth and Thermoelectric Properties of Ce5Cu19P12

MRS Proceedings ◽

10.1557/proc-545-171 ◽

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.

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The growth of sapphire single crystals

Journal of the Serbian Chemical Society ◽

10.2298/jsc0106411g ◽

2001 ◽

Vol 66 (6) ◽

pp. 411-418 ◽

Cited By ~ 4

Author(s):

Aleksandar Golubovic ◽

Slobodanka Nikolic ◽

Stevan Djuric ◽

Andreja Valcic

Keyword(s):

Crystal Growth ◽

Single Crystals ◽

Powder Diffraction ◽

Chemical Polishing ◽

Published Data ◽

Czochralski Technique ◽

Critical Rate ◽

Etching Solution ◽

X Ray ◽

Crystal Diameter

Sapphire (Al2O3) single crystals were grown by the Czochralski technique both in air and argon atmospheres. The conditions for growing sapphire single crystals were calculated by using a combination of Reynolds and Grash of numbers. Acritical crystal diameter dc = 20 mm and the critical rate of rotation c = 20 rpm were calculated from the hydrodynamics of the melt. The value of the rate of crystal growth was experimentally found to be 3.5 mm/h. According to our previous experiments, it was confirmed that three hours exposures to conc. H3PO4 at 593 K was suitable for chemical polishing. Also, three hours exposure to conc.H3PO4 at 523Kwas found to be a suitable etching solution. The lattice parameters a = 0.47573 nm and c = 1.29893 nm were determined by X-ray powder diffraction. The obtained results are discussed and compared with published data.

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Growth and Facet Orientations in Single-Phase TiAl Single Crystals

MRS Proceedings ◽

10.1557/proc-364-813 ◽

1994 ◽

Vol 364 ◽

Cited By ~ 2

Author(s):

R. Mahapatra ◽

H. Lin ◽

D. P. Pope ◽

Y. T. Chou

Keyword(s):

Crystal Growth ◽

Single Crystals ◽

Single Phase ◽

Tial Alloy ◽

Solidification Rate ◽

Floating Zone ◽

X Ray Diffraction ◽

X Ray ◽

Electron Backscattering

AbstractSingle crystals of single-phase TiAl alloy (Ti-56 at. % Al) have been grown at lOmm/h solidification rate in an ASGAL FZ-SS35W Optical Floating Zone Furnace. The orientations of the resulting single crystals have been determined using the Laue X-ray diffraction, and Electron Backscattering Pattern (EBSP) methods. A correlation between orientations of the crystal growth and grown-in facets has been established.

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The growth of Nd: YAG single crystals

Journal of the Serbian Chemical Society ◽

10.2298/jsc0204291g ◽

2002 ◽

Vol 67 (4) ◽

pp. 291-300 ◽

Cited By ~ 32

Author(s):

Aleksandar Golubovic ◽

Slobodanka Nikolic ◽

Rados Gajic ◽

Stevan Djuric ◽

Andreja Valcic

Keyword(s):

Crystal Growth ◽

Single Crystals ◽

Powder Diffraction ◽

Lattice Parameter ◽

Argon Atmosphere ◽

Published Data ◽

Czochralski Technique ◽

Critical Rate ◽

X Ray ◽

Crystal Diameter

Y3Al5O12 doped with 0.8%wt.Nd (Nd:YAG) single crystals were grown by the Czochralski technique under an argon atmosphere. The conditions for growing the Nd:YAG single crystals were calculated by using a combination of Reynolds and Grashof numbers. The critical crystal diameter and the critical rate of rotation were calculated from the hydrodynamics of the melt. The crystal diameter Dc=1.5 cm remained constant during the crystal growth while the critical rate of rotation changed from ?c=38 rpm after necking to ?c=13 rpm at the end of the crystal. The value of the rate of crystal growth was experimentally found to be 0.8?1.0 mm/h. According to our previous experiments, it was confirmed that 20 min exposure to conc. H3PO4 at 603 K was suitable for chemical polishing. Also, one-hour exposure to conc. H3PO4 at 493 K was found to be suitable for etching. The lattice parameter a=1.201 (1) nm was determined by X-ray powder diffraction. The obtained results are discussed and compared with published data.

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Growth, optical and EPR properties of Li1.72Na0.28Ge4O9 single crystals pure and slightly doped with Cr

Open Physics ◽

10.2478/s11534-011-0114-4 ◽

2012 ◽

Vol 10 (2) ◽

Cited By ~ 4

Author(s):

Anna Jasik ◽

Marek Berkowski ◽

Slawomir Kaczmarek ◽

Andrzej Suchocki ◽

Agata Kaminska ◽

...

Keyword(s):

Single Crystals ◽

Ambient Atmosphere ◽

Solid Solution Series ◽

Photoluminescence Spectra ◽

Czochralski Technique ◽

Structural Refinement ◽

X Ray Diffraction ◽

X Ray ◽

X Band ◽

Field Modulation

AbstractSingle crystals of lithium-sodium-tetragermanate, a member of the solid solution series Li2−xNaxGe4O9 with x=0.28, pure and slightly doped with Cr3+ ions (0.03 mol.% and 0.1 mol.%), were grown in ambient atmosphere by the Czochralski technique from stoichiometric melt. The crystals with dimensions up to 20 mm in diameter and 50 mm in length were obtained. The crystal structure has been determined by means of X-ray diffraction. Phase analysis and structural refinement of the Li1.72Na0.28Ge4O9 crystals were performed by X-ray powder diffraction using Ni-filtered Cu Kα radiation with a Siemens D5000 diffractometer. The absorption, excitation and photoluminescence spectra of the crystals were measured in the UV-VIS and IR range at low temperatures. EPR investigations were performed using a conventional X-band Bruker ELEXSYS E 500 CW-spectrometer operating at 9.5 GHz with 100 kHz magnetic field modulation. Temperature and angular dependences of the EPR spectra of the crystal samples were recorded in the 3–300 K temperature range.

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The growth and optical properties of Bi12SiO20 single crystals

Journal of the Serbian Chemical Society ◽

10.2298/jsc0204279g ◽

2002 ◽

Vol 67 (4) ◽

pp. 279-289 ◽

Cited By ~ 8

Author(s):

Aleksandar Golubovic ◽

Slobodanka Nikolic ◽

Rados Gajic ◽

Stevan Djuric ◽

Andreja Valcic

Keyword(s):

Crystal Growth ◽

Single Crystals ◽

Lattice Parameter ◽

Published Data ◽

Czochralski Technique ◽

Critical Rate ◽

X Ray ◽

Wave Numbers ◽

Different Temperatures ◽

Crystal Diameter

Single crystals of Bi12SiO20 were grown from the melt by the Czochralski technique. The critical crystal diameter dc=10 mm and the critical rate of rotation ?c=20 rpm were calculated by equations from the hydrodynamics of a melt. The rate of crystal growth was experimentally obtained to be 5 mm/h. The crystal growth was in the [111] direction. The lattice parameter a=1.0096nm was determined by X-ray powder diffraction. The reflectance spectra were recorded in the wave numbers range 20?5000 cm-1 at different temperatures. For all the recorded spectra the values of the vibrational TO and LO modes were found using the Kramers-Kronig analysis (KKA). Twentyfive TO and LO modes were found at 70 K, and eighteen at 295 K. The obtained results are discussed and compared with published data.

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The growth of ruby single crystals

Journal of the Serbian Chemical Society ◽

10.2298/jsc0501087g ◽

2005 ◽

Vol 70 (1) ◽

pp. 87-95 ◽

Cited By ~ 6

Author(s):

Aleksandar Golubovic ◽

Slobodanka Nikolic ◽

Stevan Djuric ◽

Andreja Valcic

Keyword(s):

Crystal Growth ◽

Single Crystals ◽

Powder Diffraction ◽

Argon Atmosphere ◽

Published Data ◽

Czochralski Technique ◽

Critical Rate ◽

Etching Solution ◽

X Ray ◽

Crystal Diameter

Ruby (Cr:Al2O3) single crystals were grown by the Czochralski technique in an argon atmosphere. The critical crystal diameter dc = 1.0 cm and the critical rate of rotation ?c = 20 rpm were calculated by equations of the hydrodynamics of the melt. The rate of crystal growth was experimentally obtained to be 2.7 mm/h. For chemical polishing, conc. H3PO4 at 593 K for an exposure of 3 hours was determined. Conc. H3PO4 at 523 K for an exposure of 3 h was found to be a suitable etching solution. The lattice parameters a = 0.47627(6) nm and c = 1.301(1) nm were determined by X-ray powder diffraction. The obtained results are discussed and compared with published data.

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