Identification of the B33 martensite phase in Cu–Zr using first-principles and X-ray diffraction

The structure, hydrogen bonding, X-ray diffraction pattern and mechanical properties of six important uranyl carbonate minerals, roubaultite, fontanite, sharpite, widenmannite, grimselite and čejkaite, are determined using first principles methods.

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First principles calculations, neutron, and x-ray diffraction investigation of Y3Ni13B2, Y3Co13B2, and Y3Ni10Co3B2

Journal of Applied Physics ◽

10.1063/1.4862163 ◽

2014 ◽

Vol 115 (2) ◽

pp. 023907

Author(s):

N. Plugaru ◽

M. Valeanu ◽

R. Plugaru ◽

J. Campo

Keyword(s):

First Principles ◽

First Principles Calculations ◽

X Ray Diffraction ◽

X Ray

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Post-Rh2O3(II)transition and the high pressure-temperature phase diagram of gallia: A first-principles and x-ray diffraction study

Physical Review B ◽

10.1103/physrevb.76.174108 ◽

2007 ◽

Vol 76 (17) ◽

Cited By ~ 18

Author(s):

Taku Tsuchiya ◽

Hitoshi Yusa ◽

Jun Tsuchiya

Keyword(s):

Phase Diagram ◽

High Pressure ◽

Diffraction Study ◽

First Principles ◽

Temperature Phase ◽

X Ray Diffraction ◽

X Ray ◽

Temperature Phase Diagram

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Crystal Structures of Al2Cu Revisited: Understanding Existing Phases and Exploring Other Potential Phases

Metals ◽

10.3390/met9101037 ◽

2019 ◽

Vol 9 (10) ◽

pp. 1037 ◽

Cited By ~ 4

Author(s):

Sai Wang ◽

Changzeng Fan

Keyword(s):

Crystal Structure ◽

High Pressure ◽

Single Crystal ◽

First Principles ◽

First Principles Calculations ◽

X Ray Diffraction ◽

X Ray ◽

Structural Relationships ◽

Al2cu Phase ◽

High Pressure Sintering

When processing single crystal X-ray diffraction datasets for twins of Al2Cu sample synthesized by the high-pressure sintering (HPS) method, we have clarified why the crystal structure of Al2Cu was incorrectly solved about a century ago. The structural relationships between all existing Al2Cu phases, including the Owen-, θ-, θ’-, and Ω-Al2Cu phases, were investigated and established based on a proposed pseudo Al2Cu phase. Two potential phases have been built up by adjusting the packing sequences of A/B layers of Al atoms that were inherent in all existing Al2Cu phases. The mechanical, thermal, and dynamical stability of two such novel phases and their electronic properties were investigated by first-principles calculations.

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New Insights on the Reversible Lithiation Mechanism of TiO2(B) by Operando X-ray Absorption Spectroscopy and X-ray Diffraction Assisted by First-Principles Calculations

The Journal of Physical Chemistry C ◽

10.1021/jp507574e ◽

2014 ◽

Vol 118 (47) ◽

pp. 27210-27218 ◽

Cited By ~ 17

Author(s):

Marcus Fehse ◽

Mouna Ben Yahia ◽

Laure Monconduit ◽

Frédéric Lemoigno ◽

Marie-Liesse Doublet ◽

...

Keyword(s):

Absorption Spectroscopy ◽

First Principles ◽

First Principles Calculations ◽

X Ray Diffraction ◽

X Ray ◽

X Ray Absorption

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Structural analysis of Gd6FeBi2 from single-crystal X-ray diffraction methods and electronic structure calculations

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229619004868 ◽

2019 ◽

Vol 75 (5) ◽

pp. 562-567 ◽

Cited By ~ 4

Author(s):

Jiliang Zhang ◽

Yong-Mook Kang ◽

Guangcun Shan ◽

Svilen Bobev

Keyword(s):

Electronic Structure ◽

Single Crystal ◽

First Principles ◽

Earth Metal ◽

Magnetic Ordering ◽

Additional Contribution ◽

First Principles Calculations ◽

X Ray Diffraction ◽

Magnetic Exchange ◽

X Ray

The crystal structure of the gadolinium iron bismuthide Gd6FeBi2 has been characterized by single-crystal X-ray diffraction data and analyzed in detail using first-principles calculations. The structure is isotypic with the Zr6CoAl2 structure, which is a variant of the ZrNiAl structure and its binary prototype Fe2P (Pearson code hP9, Wyckoff sequence g f d a). As such, the structure is best viewed as an array of tricapped trigonal prisms of Gd atoms centered alternately by Fe and Bi. The magnetic-ordering temperature of this compound (ca 350 K) is much higher than that of other rare-earth metal-rich phases with the same or related structures. It is also higher than the ordering temperature of many other Gd-rich ternary phases, where the magnetic exchange is typically governed by Ruderman–Kittel–Kasuya–Yosida (RKKY) interactions. First-principles calculations reveal a larger than expected Gd magnetic moment, with the additional contribution arising from the Gd 5d electrons. The electronic structure analysis suggests strong Gd 5d–Fe 3d hybridization to be the cause of this effect, rather than weak interactions between Gd and Bi. These details are of importance for understanding the magnetic response and explaining the high ordering temperature in this material.

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Powder X-ray diffraction of Metastudtite, (UO2)O2(H2O)2

Powder Diffraction ◽

10.1017/s0885715615000895 ◽

2016 ◽

Vol 31 (1) ◽

pp. 71-72 ◽

Cited By ~ 3

Author(s):

Mark A. Rodriguez ◽

Philippe E. Weck ◽

Joshua D. Sugar ◽

Thomas J. Kulp

Keyword(s):

Powder Diffraction ◽

Diffraction Data ◽

First Principles ◽

Density Functional ◽

Powder Diffraction Data ◽

Structural Refinement ◽

X Ray Diffraction ◽

Orthorhombic Space Group ◽

X Ray ◽

Unit Cells

There has been some confusion in the published literature concerning the structure of Metastudtite (UO2)O2(H2O)2 where differing unit cells and space groups have been cited for this compound. Owing to the absence of a refined structure for Metastudtite, Weck et al. (2012) have documented a first-principles study of Metastudtite using density functional theory (DFT). Their model presents the structure of Metastudtite as an orthorhombic (space group Pnma) structure with lattice parameters of a = 8.45, b = 8.72, and c = 6.75 Å. A Powder Diffraction File (PDF) database entry has been allocated for this hypothetical Metastudtite phase based on the DFT modeling (see 01-081-9033) and aforementioned Dalton Trans. manuscript. We have obtained phase pure powder X-ray diffraction data for Metastudtite and have confirmed the model of Weck et al. via Rietveld refinement (see Figure 1). Structural refinement of this powder diffraction dataset has yielded updated refined parameters. The new cell has been determined as a = 8.411(1), b = 8.744(1), and c = 6.505(1) Å; cell volume = 478.39 Å3. There are only subtle differences between the refined structure and that of the first-principles model derived from DFT. Notably, the b-axis is significantly contracted in the final refinement as compared with DFT. There were also subtle changes to the U1, O1, and O3 atom positions. Tabulated powder diffraction data (d's and I's) for the Metastudtite have been derived from the refined model and these new values can serve to augment the PDF entry 01-081-9033 with a more updated entry based on observed X-ray powder diffraction data.

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First-principles, UV Raman, X-ray diffraction and TEM study of the structure and lattice dynamics of the diamond–lonsdaleite system

Diamond and Related Materials ◽

10.1016/j.diamond.2011.05.013 ◽

2011 ◽

Vol 20 (7) ◽

pp. 951-953 ◽

Cited By ~ 20

Author(s):

V.N. Denisov ◽

B.N. Mavrin ◽

N.R. Serebryanaya ◽

G.A. Dubitsky ◽

V.V. Aksenenkov ◽

...

Keyword(s):

First Principles ◽

Lattice Dynamics ◽

X Ray Diffraction ◽

X Ray ◽

Uv Raman

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THE Ge(001) SURFACE RECONSTRUCTION: DFT AND MCS

Surface Review and Letters ◽

10.1142/s0218625x9900113x ◽

1999 ◽

Vol 06 (06) ◽

pp. 1045-1051 ◽

Cited By ~ 11

Author(s):

YOSHIHIDE YOSHIMOTO ◽

YOSHIMICHI NAKAMURA ◽

HIROSHI KAWAI ◽

MASARU TSUKADA ◽

MASATOSHI NAKAYAMA

Keyword(s):

Phase Transition ◽

First Principles ◽

Density Functional ◽

First Principles Calculation ◽

Transient Temperature ◽

Diffraction Experiment ◽

X Ray Diffraction ◽

Functional Theory ◽

Flip Flop ◽

X Ray

The problem of relative energetic stabilities of the high order reconstructions of the Ge(001) surface is revisited by a more refined first-principles calculation based on density functional theory. Using this result, we performed a Monte Carlo simulation of the phase transition, and obtained 315 K as the transition temperature of p(2× 1) → c(4× 2). This reproduces fairly well the transient temperature (250–350 K) observed by an X-ray diffraction experiment. The obtained geometry of the c(4× 2) structure compares well with an X-ray diffraction experiment. The potential energy curves of flip-flop motions of both single dimer and dimer in type-P defect are also obtained.

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