Electron Deficiency but Semiconductive Diamond-like B2CN Originated from Three-Center Bonds

2021 ◽  
Author(s):  
Xinxin Zhang ◽  
Guoliang Yu ◽  
Hui Chen ◽  
Yu Zhao ◽  
Tai-Min Cheng ◽  
...  
Keyword(s):  
Superhard Material ◽  
Light Element ◽  
Metallic Character ◽  
Electron Deficiency

B2CN was one of the synthesized light element compounds, which was expected to be superhard material with metallic character due to its electron deficiency nature. However, in this work we discovered...

Computer programs for the calculation of x-ray intensities emitted by elements in multi-layer structures

1990 ◽  
Vol 48 (2) ◽  
pp. 216-217
Author(s):  
G.F. Bastin ◽  
H.J.M. Heijligers ◽  
J.M. Dijkstra
Keyword(s):  
Software Package ◽  
Light Element ◽  
Matrix Correction ◽  
Excellent Performance ◽  
Element Analysis ◽  
X Ray ◽  
Know How ◽  
Accurate Knowledge ◽  
Layer Structures ◽  
Bulk Matrix

For the calculation of X-ray intensities emitted by elements present in multi-layer systems it is vital to have an accurate knowledge of the x-ray ionization vs. mass-depth (ϕ(ρz)) curves as a function of accelerating voltage and atomic number of films and substrate. Once this knowledge is available the way is open to the analysis of thin films in which both the thicknesses as well as the compositions can usually be determined simultaneously.Our bulk matrix correction “PROZA” with its proven excellent performance for a wide variety of applications (e.g., ultra-light element analysis, extremes in accelerating voltage) has been used as the basis for the development of the software package discussed here. The PROZA program is based on our own modifications of the surface-centred Gaussian ϕ(ρz) model, originally introduced by Packwood and Brown. For its extension towards thin film applications it is required to know how the 4 Gaussian parameters α, β, γ and ϕ(o) for each element in each of the films are affected by the film thickness and the presence of other layers and the substrate.

The Influence of Specimen Thickness in Quantitative Electron Energy Loss Spectroscopy

1980 ◽  
Vol 38 ◽  
pp. 112-113
Author(s):  
Nestor J. Zaluzec
Keyword(s):  
Quantitative Analysis ◽  
Adverse Effects ◽  
Energy Loss ◽  
Electron Energy ◽  
Electron Energy Loss Spectroscopy ◽  
Materials Science ◽  
Light Element ◽  
Specimen Thickness ◽  
Element Analysis ◽  
Electron Energy Loss

The application of electron energy loss spectroscopy (EELS) to light element analysis is rapidly becoming an important aspect of the microcharacterization of solids in materials science, however relatively stringent requirements exist on the specimen thickness under which one can obtain EELS data due to the adverse effects of multiple inelastic scattering.1,2 This study was initiated to determine the limitations on quantitative analysis of EELS data due to specimen thickness.

scholarly journals New Radical Cation Salts Based on BDH-TTP Donor: Two Stable Molecular Metals with a Magnetic [ReF6]2− Anion and a Semiconductor with a [ReO4]− Anion

2021 ◽  
Vol 7 (4) ◽  
pp. 54
Author(s):  
Nataliya D. Kushch ◽  
Gennady V. Shilov ◽  
Lev I. Buravov ◽  
Eduard B. Yagubskii ◽  
Vladimir N. Zverev ◽  
...  
Keyword(s):  
Radical Cation ◽  
Low Temperatures ◽  
Ac Susceptibility ◽  
Slow Relaxation ◽  
Organic Radical ◽  
Inorganic Anion ◽  
Distinctive Features ◽  
Metallic Character ◽  
Radical Cation Salts ◽  
Partial Population

Three radical cation salts of BDH-TTP with the paramagnetic [ReF6]2− and diamagnetic [ReO4]− anions have been synthesized: κ-(BDH-TTP)4ReF6 (1), κ-(BDH-TTP)4ReF6·4.8H2O (2) and pseudo-κ″-(BDH-TTP)3(ReO4)2 (3). The crystal and band structures, as well as the conducting properties of the salts, have been studied. The structures of the three salts are layered and characterized by alternating κ-(1, 2) and κ″-(3) type organic radical cation layers with inorganic anion sheets. Similar to other κ-salts, the conducting layers in the crystals of 1 and 2 are formed by BDH-TTP dimers. The partial population of positions of Re atoms and disorder in the anionic layers of 1–3 are their distinctive features. Compounds 1 and 2 show the metallic character of conductivity down to low temperatures, while 3 is a semiconductor. The ac susceptibility of crystals 1 was investigated in order to test the possible slow relaxation of magnetization associated with the [ReF6]2− anion.

Heavy nitrogen in Bencubbin—a light-element isotopic anomaly in a stony-iron meteorite

Nature ◽  
1986 ◽  
Vol 323 (6084) ◽  
pp. 138-140 ◽  
Author(s):  
I. A. Franchi ◽  
I. P. Wright ◽  
C. T. Pillinger
Keyword(s):  
Light Element ◽  
Iron Meteorite ◽  
Isotopic Anomaly ◽  
Heavy Nitrogen

scholarly journals Machine Learning: Finding the Next Superhard Material through Ensemble Learning (Adv. Mater. 5/2021)

2021 ◽  
Vol 33 (5) ◽  
pp. 2170034
Author(s):  
Ziyan Zhang ◽  
Aria Mansouri Tehrani ◽  
Anton O. Oliynyk ◽  
Blake Day ◽  
Jakoah Brgoch
Keyword(s):  
Machine Learning ◽  
Ensemble Learning ◽  
Superhard Material

A method for investigation of light-element distribution in the surface layers of semiconductors and dielectrics

1992 ◽  
Vol 7 (7) ◽  
pp. 881-887 ◽  
Author(s):  
G M Gusinskii ◽  
I V Kudryavtsev ◽  
V K Kudoyarova ◽  
V O Naidenov ◽  
L A Rassadin
Keyword(s):  
Light Element ◽  
Element Distribution ◽  
Surface Layers

X-ray Raman Spectroscopy of Carbon in Asphaltene:  Light Element Characterization with Bulk Sensitivity

2000 ◽  
Vol 72 (11) ◽  
pp. 2609-2612 ◽  
Author(s):  
Uwe Bergmann ◽  
Oliver C. Mullins ◽  
S. P. Cramer
Keyword(s):  
Raman Spectroscopy ◽  
Light Element ◽  
X Ray

Electrically active light-element complexes in silicon crystals grown by cast method

2016 ◽  
Vol 55 (9) ◽  
pp. 095502
Author(s):  
Kuniyuki Sato ◽  
Atsushi Ogura ◽  
Haruhiko Ono
Keyword(s):  
Light Element ◽  
Silicon Crystals

scholarly journals Light element abundance inhomogeneities in globular clusters: probing star formation and evolution in the early Milky Way

1994 ◽  
Vol 72 (11-12) ◽  
pp. 772-781 ◽  
Author(s):  
Michael M. Briley ◽  
Roger A. Bell ◽  
James E. Hesser ◽  
Graeme H. Smith
Keyword(s):  
Star Formation ◽  
Globular Clusters ◽  
Main Sequence ◽  
Light Element ◽  
Star Formation History ◽  
Element Abundance ◽  
Chemical Compositions ◽  
Original Material ◽  
Abundance Patterns ◽  
Red Giant

Abundance patterns of the elements C, N, and O are sensitive probes of stellar nucleosynthesis processes and, in addition, O abundances are an important input for stellar age determinations. Understanding the nature of the observed distribution of these elements is key to constraining protogalactic star formation history. Patterns deduced from low-resolution spectroscopy of the CN, CH, NH, and CO molecules for low-mass stars in their core-hydrogen or first shell-hydrogen burning phases in the oldest ensembles known, the Galactic globular star clusters, are reviewed. New results for faint stars in NGC 104 (47 Tuc, C0021-723) reveal that the bimodal, anticorrelated pattern of CN and CH strengths found among luminous evolved stars is also present in stars nearing the end of their main-sequence lifetimes. In the absence of known mechanisms to mix newly synthesized elements from the interior to the observable surface layers of such unevolved stars, those particular inhomogeneities imply that the original material from which the stars formed some 15 billion years ago was chemically inhomogeneous in the C and N elements. However, in other clusters, observations of abundance ratios and C isotope ratios suggest that alterations to surface chemical compositions are produced as stars evolve from the main sequence through the red giant branch. Thus, the current observed distributions of C, N, and O among the brightest stars (those also observed most often) may not reflect the true distribution from which the protocluster cloud formed. The picture that is emerging of the C, N, and O abundance patterns within globular clusters may be one which requires a complicated combination of stellar evolutionary and primordial effects for its explanation.

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