2014 Defects in Semiconductors Gordon Research Conference & Gordon Research Seminar. Research Area 1: Materials Science, 1.3 Physical Properties of Materials

Experimental charge-density analysis towards predictive materials science

Journal of Experimental Techniques and Instrumentation ◽

10.30609/jeti.v4i03.12820 ◽

2021 ◽

Vol 4 (03) ◽

pp. 50-71

Author(s):

Leonardo Dos Santos ◽

Bernardo L. Rodrigues ◽

Camila B. Pinto

Keyword(s):

Physical Properties ◽

Charge Density ◽

Materials Science ◽

New Materials ◽

Wide Applicability ◽

Density Analysis ◽

Properties Of Materials ◽

A Charge ◽

Experimental Charge Density

The ongoing increase in the number of experimental charge-density studies can be related to both the technological advancements and the wide applicability of the method. Regarding materials science, the understanding of bonding features and their relation to the physical properties of materials can not only provide means to optimize such properties, but also to predict and design new materials with the desired ones. In this tutorial, we describe the steps for a charge-density analysis, emphasizing the most relevant features and briefly discussing the applications of the method.

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Everything you've always wanted to know about what your students think they know but were afraid to ask.

MRS Proceedings ◽

10.1557/proc-proc-632-hh3.2 ◽

2000 ◽

Vol 632 ◽

Author(s):

Eric Werwa

Keyword(s):

Materials Science ◽

Science Museum ◽

Science And Engineering ◽

Museum Exhibit ◽

Museum Visitors ◽

The Public ◽

Materials Science And Engineering ◽

Properties Of Materials ◽

Formal Science ◽

Lay Public

ABSTRACTA review of the educational literature on naive concepts about principles of chemistry and physics and surveys of science museum visitors reveal that people of all ages have robust alternative notions about the nature of atoms, matter, and bonding that persist despite formal science education experiences. Some confusion arises from the profound differences in the way that scientists and the lay public use terms such as materials, metals, liquids, models, function, matter, and bonding. Many models that eloquently articulate arrangements of atoms and molecules to informed scientists are not widely understood by lay people and may promote naive notions among the public. Shifts from one type of atomic model to another and changes in size scales are particularly confusing to learners. People's abilities to describe and understand the properties of materials are largely based on tangible experiences, and much of what students learn in school does not help them interpret their encounters with materials and phenomena in everyday life. Identification of these challenges will help educators better convey the principles of materials science and engineering to students, and will be particularly beneficial in the design of the Materials MicroWorld traveling museum exhibit.

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Topological electronics

Communications Physics ◽

10.1038/s42005-021-00569-5 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Matthew J. Gilbert

Keyword(s):

Information Processing ◽

Physical Properties ◽

Materials Science ◽

Electronic Device ◽

Condensed Matter ◽

Topological Phases ◽

Applied Physics ◽

New Paradigm ◽

Topological Materials ◽

Device Applications

AbstractWithin the broad and deep field of topological materials, there are an ever-increasing number of materials that harbor topological phases. While condensed matter physics continues to probe the exotic physical properties resulting from the existence of topological phases in new materials, there exists a suite of “well-known” topological materials in which the physical properties are well-characterized, such as Bi2Se3 and Bi2Te3. In this context, it is then appropriate to ask if the unique properties of well-explored topological materials may have a role to play in applications that form the basis of a new paradigm in information processing devices and architectures. To accomplish such a transition from physical novelty to application based material, the potential of topological materials must be disseminated beyond the reach of condensed matter to engender interest in diverse areas such as: electrical engineering, materials science, and applied physics. Accordingly, in this review, we assess the state of current electronic device applications and contemplate the future prospects of topological materials from an applied perspective. More specifically, we will review the application of topological materials to the general areas of electronic and magnetic device technologies with the goal of elucidating the potential utility of well-characterized topological materials in future information processing applications.

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Self Assembling Nanostructured Delivery Vehicles for Biochemically Reactive Pairs

MRS Proceedings ◽

10.1557/proc-351-109 ◽

1994 ◽

Vol 351 ◽

Author(s):

Nir Kossovsky ◽

A. Gelman ◽

H.J. Hnatyszyn ◽

E. Sponsler ◽

G.-M. Chow

Keyword(s):

Physical Properties ◽

Self Assembly ◽

Materials Science ◽

Technology Development ◽

Biological Behavior ◽

X Ray Diffraction ◽

Self Assembling ◽

Transmission Electron ◽

Carbon Ceramic

ABSTRACTIntrigued by the deceptive simplicity and beauty of macromolecular self-assembly, our laboratory began studying models of self-assembly using solids, glasses, and colloidal substrates. These studies have defined a fundamental new colloidal material for supporting members of a biochemically reactive pair.The technology, a molecular transportation assembly, is based on preformed carbon ceramic nanoparticles and self assembled calcium-phosphate dihydrate particles to which glassy carbohydrates are then applied as a nanometer thick surface coating. This carbohydrate coated core functions as a dehydroprotectant and stabilizes surface immobilized members of a biochemically reactive pair. The final product, therefore, consists of three layers. The core is comprised of the ceramic, the second layer is the dehydroprotectant carbohydrate adhesive, and the surface layer is the biochemically reactive molecule for which delivery is desired.We have characterized many of the physical properties of this system and have evaluated the utility of this delivery technology in vitro and in animal models. Physical characterization has included standard and high resolution transmission electron microscopy, electron and x-ray diffraction and ζ potential analysis. Functional assays of the ability of the system to act as a nanoscale dehydroprotecting delivery vehicle have been performed on viral antigens, hemoglobin, and insulin. By all measures at present, the favorable physical properties and biological behavior of the molecular transportation assembly point to an exciting new interdisciplinary area of technology development in materials science, chemistry and biology.

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Symmetry-general ab initio computation of physical properties using quantum software integrated with crystal structure databases: results and perspectives

Acta Crystallographica Section B Structural Science ◽

10.1107/s0108768102002422 ◽

2002 ◽

Vol 58 (3) ◽

pp. 349-357 ◽

Cited By ~ 8

Author(s):

Yvon Le Page ◽

Paul W. Saxe ◽

John R. Rodgers

Keyword(s):

Crystal Structure ◽

Physical Properties ◽

Ab Initio ◽

Materials Science ◽

Science Research ◽

Elastic Tensor ◽

Pure Phase ◽

Simulation And Experiment ◽

Structure Databases ◽

Using Data

The timely integration of crystal structure databases, such as CRYSTMET, ICSD etc., with quantum software, like VASP, OresteS, ElectrA etc., allows ab initio cell and structure optimization on existing pure-phase compounds to be performed seamlessly with just a few mouse clicks. Application to the optimization of rough structure models, and possibly new atomic arrangements, is detailed. The ability to reproduce observed cell data can lead to an assessment of the intrinsic plausibility of a structure model, even without a competing model. The accuracy of optimized atom positions is analogous to that from routine powder studies. Recently, the ab initio symmetry-general least-squares extraction of the coefficients of the elastic tensor for pure-phase materials using data from corresponding entries in crystal structure databases was automated. A selection of highly encouraging results is presented, stressing the complementarity of simulation and experiment. Additional physical properties also appear to be computable using existing quantum software under the guidance of an automation scheme designed following the above automation for the elastic tensor. This possibility creates the exciting perspective of mining crystal structure databases for new materials with combinations of physical properties that were never measured before. Crystal structure databases can accordingly be expected to become the cornerstone of materials science research within a very few years, adding immense practical value to the archived structure data.

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Targeted Alternation in Properties of Solid Amorphous-Nanocrystalline Material in Exposing to Nanosecond Laser Radiation

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.410.469 ◽

2021 ◽

Vol 410 ◽

pp. 469-474

Author(s):

Ivan S. Safronov ◽

Alexander I. Ushakov

Keyword(s):

Laser Radiation ◽

Physical Properties ◽

Materials Science ◽

Chemical Properties ◽

High Energy ◽

Strength Properties ◽

Nanosecond Laser ◽

Processing Modes ◽

Traditional Processing ◽

Physical And Chemical

One of the most important purposes of materials science is the ability to govern the physical properties of materials characterized by different structures. The strength properties of nanostructured metal alloys do not always meet the exploitation requirements. The set of properties of such materials is stable within narrow limits: temperature, mechanical, and corrosion conditions. Traditional processing modes are ineffective for such materials. Attempts to use them often lead to the loss of unique physical and chemical properties. The most effective methods of processing such materials are associated with the use of laser radiation. The laser pulse has a number of features, including a complex effect on the surface layers of the material. Spot and short irradiation with high-energy rays can preserve the unique physical properties of samples as a whole and improve strength indicators without destroying the structure of the material as a whole.

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