Morphology of Bi2O3 Nanowires and Nanoflowers in the Synthesis of MnBi Alloys

High temperature phase (HTP) MnBi alloys were formed using the arc-melting method. The drastic difference in the melting points of Mn and Bi resulted in non-homogeneity. The MnBi, Mn, Bi and O were detected by energy dispersive spectrometry (EDS). The field emission scanning electron microscope (FESEM) revealed the morphology of each phase. The rod-like and flower-like nanostructures were consistent with Bi2O3 as indicated by EDS and X-ray diffactometry. The HTP MnBi was transformed to the low temperature phase (LTP) following the annealing process. The remaining Bi and Mn are susceptible to oxidation leading to the subsequent formation of Bi2O3 as well as MnO. Whereas LTP MnBi alloys are useful for their hard magnetic properties, Bi2O3 nanowire is receiving attention for potential applications in optoelectronic devices.

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On the Phase Transition of Bis(pyridinium)hexachlorometallates, (C5H5NH)2[MCl6], M = Sn, Te, Pb, Pt. An X-Ray and 35Cl NQR Study

Zeitschrift für Naturforschung A ◽

10.1515/zna-1987-0714 ◽

1987 ◽

Vol 42 (7) ◽

pp. 739-748 ◽

Cited By ~ 1

Author(s):

Dirk Borchers ◽

Alarich Weiss

Keyword(s):

Crystal Structure ◽

Phase Transition ◽

Phase Ii ◽

High Temperature Phase ◽

Temperature Phase ◽

X Ray ◽

Lattice Constants ◽

Pyridinium Ring ◽

35Cl Nqr ◽

Low Temperature Phase

A phase transition has been observed in bis(pyridinium) hexachlorometallates (C5H5NH)2[MIVCl6]. M = Sn. Te. Pb. Pt. The crystal structure of the low temperature phase II of the salt with M = Sn was determined, space group C 1ḷ- P 1̅, Z = 1 (a = 734.1pm, b = 799.0 pm, c = 799.7 pm,α= 83.229°. β = 65.377°, γ= 84.387°, T = 297 K). The four compounds are isotypic in phase II as well as in the high temperature phase I (C2H2-B2 /m, Z = 2) for which the crystal structure is known for M = Te . The lattice constants of all compounds (both phases) are given. The temperature dependence of the 35Cl NQR spectrum was investigated. The three line 35Cl NQR spectrum is in agreement with the crystal structure. The dynamics of the pyridinium ring shows up in a fade out of part of the 35Cl NQR spectrum . The influence o f H ↔ D exchange on 35Cl NQR is studied and an assignment of ν (35Cl) ↔ Cl(i) is proposed. The nature of the phase transition P1̅ (Z = 1) ↔ B2 /m (Z = 2) is discussed.

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Formation of the high temperature phase in vacuum deposited SnSe thin films

Zeitschrift für Kristallographie - Crystalline Materials ◽

10.1524/zkri.1986.175.1-2.37 ◽

1986 ◽

Vol 175 (1-2) ◽

Cited By ~ 2

Author(s):

T. Subba Rao ◽

B. K. Samantaray ◽

A. K. Chaudhuri

Keyword(s):

Thin Films ◽

High Temperature ◽

High Temperature Phase ◽

Temperature Phase ◽

X Ray Diffraction ◽

X Ray ◽

Glass Substrates ◽

Different Temperatures ◽

Substrate Temperatures ◽

Low Temperature Phase

AbstractThin films of SnSe vacuum deposited on glass substrates kept at different temperatures have been studied by X-ray diffraction. It is observed that the high temperature phase of SnSe, usually found above 807 K is frozen in along with the low temperature phase when deposited at substrate temperatures of 473 K and above.

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Phase Transitions and Distortion of [BiCl6]3– Octahedra in (C3H5NH3)3[BiCl6] – DSC and Single-Crystal X-Ray Diffraction Studies

Zeitschrift für Naturforschung B ◽

10.1515/znb-2004-0913 ◽

2004 ◽

Vol 59 (9) ◽

pp. 1029-1034 ◽

Cited By ~ 7

Author(s):

Bartosz Zarychta ◽

Maciej Bujak ◽

Jacek Zaleski

Keyword(s):

Phase Transition ◽

High Temperature Phase ◽

Temperature Phase ◽

X Ray Diffraction ◽

X Ray ◽

Unit Cells ◽

Temperature Phase Transition ◽

The Relationship ◽

Low Temperature Phase ◽

Disorder Type

The DSC diagram of tris(allylammonium) hexachlorobismuthate(III), (C3H5NH3)3[BiCl6], revealed three anomalies at 152, 191 and 299 K. The structure of the salt was determined at 200 and 315 K, below and above the high-temperature phase transition at 299 K. In both phases the crystals are monoclinic. At 200 K the space group is C2/c whereas at 315 K it is C2/m. The structures, at both temperatures, are composed of [BiCl6]3− octahedra and allylammonium cations. The organic and inorganic moieties are attracted to each other by a network of the N-H. . .Cl hydrogen bonds. The relationship between corresponding parameters of the unit cells has been found. The phase transition at 299 K, of the order-disorder type, is attributed to the ordering of one non-equivalent allylammonium cation in the low-temperature phase.

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Tetraalkylammonium Tetrachlorothallates (III); X-Ray, 35Cl-NQR, and 1H-NMR Studies

Zeitschrift für Naturforschung A ◽

10.1515/zna-1991-0906 ◽

1991 ◽

Vol 46 (9) ◽

pp. 777-784 ◽

Cited By ~ 9

Author(s):

Marco Lenck ◽

Shi-qi Dou ◽

Alarich Weiss

Keyword(s):

Crystal Structure ◽

Phase Ii ◽

Room Temperature ◽

High Temperature Phase ◽

Temperature Phase ◽

Nmr Studies ◽

X Ray ◽

H Nmr ◽

35Cl Nqr ◽

Low Temperature Phase

AbstractThe crystal structure of (CH3)4NTlCl4 and (C2H5)4NTlCl4 was determined at room temperature by single crystal technique. (CH3)4NTlCl4: D2h17-Cmmm; Z = 2; a = 913.2pm, b = 894.6 pm, c = 752.5 pm; (C2H5)4NTlCl4: C6v4-P63mc; Z = 2; a = 827.9 pm, c = 1329.8 pm. (C2H5)4NTlCl4 is isomorphous with (C2H5)4NInCl4. The compounds undergoe a phase transition at 239 K and 222 K, respectively. For both compounds no35 Cl NQR signal was observable in the high temperature phase I due to the dynamics of the anion. The 35 Cl NQR was studied in the low temperature phase II of both compounds as a function of temperature. (CH3)4NTlCl4 shows a two line, (C2H5)4NTlCl4 a four line spectrum. The possible phase II structures and the dynamics of the cation, studied by 1H-NMR, are discussed

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Solvothermal synthesis and magnetic properties of β-Co2P nanorods

Materials Science-Poland ◽

10.1515/msp-2015-0049 ◽

2015 ◽

Vol 33 (2) ◽

pp. 312-316 ◽

Cited By ~ 2

Author(s):

Tian Li ◽

Jun Peng Liao ◽

Ying Feng Wang

Keyword(s):

High Temperature Phase ◽

Photoemission Spectroscopy ◽

Temperature Phase ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Chloride Hexahydrate ◽

Cobalt Chloride Hexahydrate ◽

Composition Structure ◽

Low Temperature Phase

AbstractHexagonal high temperature phase β-Co2P nanorods with a diameter of around 50 nm were synthesized via a mild solvothermal route. The reaction was carried out at 180 °C using cobalt chloride hexahydrate (CoCl2 · 6H2O) as Co source and yellow phosphorous as P source. The composition, structure as well as morphology were characterized by X-ray diffraction (XRD), X-ray photoemission spectroscopy (XPS) and transmission electron microscopy (TEM). The magnetic susceptibility curve indicates that the β-Co2P nanorods show canted antiferromagnetic state, different from the paramagnetic state of orthorhombic low temperature phase β-Co2P.

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Formation process of periodic non-conservative antiphase boundary structure in L-Pd5Ce

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100173947 ◽

1990 ◽

Vol 48 (4) ◽

pp. 162-163

Author(s):

Masaru Itakura ◽

Noriyuki Kuwano ◽

Kensuke Oki

Keyword(s):

Formation Process ◽

Domain Size ◽

Antiphase Boundary ◽

Boundary Structure ◽

Temperature Phase ◽

Arc Melting ◽

Iced Water ◽

Antiphase Domains ◽

Low Temperature Phase ◽

Degree Of Order

The low temperature phase of Pd5Ce (L-Pd5Ce) has a one-dimensional long period superstructure (1D-LPS) derived from Ll2. The periodic antiphase boundaries (APBs) are parallel to (110) planes and have a shift vector of 1/2[110]. Hereafter, the indices are referred to the basic lattices of Ll2 As insertion of the APB causes a change in composition, such an APB is called “non-conservative”. Then, a domain size M depends upon the Ce concentration in the alloy. It was found that M increases also with temperature. The temperature dependency of M is attributed to a change of the degree of order within the antiphase domains. In this work, morphology of the non-conservative APBs is observed to clarify the formation process of the 1D-LPS.The alloy of Pd-16.7 at%Ce was prepared by arc melting in argon atmosphere. Disc specimens made from the alloy ingot were first held at 985 K for 260 ks and quenched in iced water to obtain the state of M=∞ or Ll2, followed by annealing for various lengths of time. The annealing temperature was 873 K where the equilibrium value for M is about 3 in unit of (110) lattice spacing of Ll2. Observation was carried out using microscopes JEM-2000FX, JEM-4000EX (HVEM Lab., Kyushu Univ.) and JEM-2000EX (Dept. of Mater. Sci. Tech., Kyushu Univ.).

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