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Journal of Materials Science and Nanotechnology | Volume 3

February 25-26, 2019 | Paris, France

Materials Science and Engineering

International Conference on

Using computational simulations to support structural characterization of metals, alloys, and

intermetallic compounds with solid-state NMR

Ary R Ferreira

Universidade Federal de Sao Carlos (UFSCar), Brazil

he use of solid-state nuclear magnetic resonance (ssNMR)

spectroscopy in materials science has boomed in recent

years. What makes it a new valuable tool for the development

of the next generation of materials, providing new insights into

atomic arrangement and electronic structure of solid samples.

Naturally, there is no denying that this ismainly due to advances

in ssNMR techniques and the high-resolution spectra that can

be obtained nowadays. Nevertheless, one cannot rule out

the important role of density functional theory (DFT) based

computational simulations in that context. With a highlight

to the gauge-including projector augmented-wave (GIPAW)

method.

It is nothing new that the aid of DFT-GIPAW calculations may be

crucial for unambiguous ssNMR peak assignments in a number

of cases. Whether it is a matter of structural intricacy like static

disorder, mixture of phases, or chemical exchange processes;

or due to a combination of distinct magnetic screening

mechanisms (MSMs) resulting from different aspects of the

electron charge and spin densities around target nuclei. That

combination of MSMs is precisely one of the biggest challenges

in the interpretation of the spectra of materials in which, in

the presence of the applied external magnetic field, electrons

define the local environment of target nuclei behaving not only

as moving charges, but also as particles with spin ½.

Withafocusonthe27Alnuclideinweaklymagneticintermetallic

compounds and in a bulk glass alloy, the aim of the current

research is to show that DFT-GIPAW calculations of orbital

and Fermi-contact shifts can not only promote a less unbiased

interpretation of the respective ssNMR spectra, but also

demonstrate the possibility of expanding out the applicability

of that type of spectroscopy to a new class of materials.