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Computational Studies of Magnetically Doped Semiconductor Nanoclusters.

Record Type:	Language materials, manuscript : Monograph/item
Title/Author:	Computational Studies of Magnetically Doped Semiconductor Nanoclusters./
Author:	Gutsev, Lavrenty Gennady.
Description:	1 online resource (170 pages)
Notes:	Source: Dissertation Abstracts International, Volume: 78-11(E), Section: B.
Subject:	Chemistry. -
Online resource:	click for full text (PQDT)
ISBN:	9781369863819

Computational Studies of Magnetically Doped Semiconductor Nanoclusters.
Gutsev, Lavrenty Gennady.

Computational Studies of Magnetically Doped Semiconductor Nanoclusters. - 1 online resource (170 pages)

Source: Dissertation Abstracts International, Volume: 78-11(E), Section: B.

Thesis (Ph.D.)--The Florida State University, 2017.

Includes bibliographical references

Spin-polarized unrestricted density functional theory is used to calculate the molecular properties of magnetic semiconductor quantum dots doped with 3d-metal atoms. We calculate total energies of the low spin antiferromagnetically coupled states using a spin-flipping algorithm leading to the broken-symmetry states. Given the novel nature of the materials studied, we simulate experimental observables such as hyperfine couplings, ionization/ energies, electron affinities, first and second order polarizabilities, band gaps and exchange coupling constants. Specifically, we begin our investigation with pure clusters of (CdSe )16 and demonstrate the dependence of molecular observables on geometrical structures. We also show that the many isomers of this cluster are energetically quite closely spaced, and thus it would be necessary to employ a battery of tests to experimentally distinguish them. Next, we discuss Mn-doping into the cage (CdSe)9 cluster as well as the zinc-blende stacking type cluster (CdSe)36. We show that the local exchange coupling mechanism is ligand-mediated superexchange and simulate the isotropic hyperfine constants. Finally, we discuss a novel study where (CdSe)9 is doped with Mn or Fe up to a full replacement of all the Cd's and discuss the transition points for the magnetic behavior and specifically the greatly differing band-gap shifts. We also outline an unexpected pattern in the polarizability of the material as metals are added and compare our results with the results from theoretical studies of the bulk material.

Electronic reproduction.
Ann Arbor, Mich. :
ProQuest,
2018

Mode of access: World Wide Web

ISBN: 9781369863819Subjects--Topical Terms:

593913
Chemistry.
Index Terms--Genre/Form:

554714
Electronic books.

Computational Studies of Magnetically Doped Semiconductor Nanoclusters.
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035 $a AAI10261223
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100 1 $a Gutsev, Lavrenty Gennady. $3 1187194
245 1 0 $a Computational Studies of Magnetically Doped Semiconductor Nanoclusters.
264 0 $c 2017
300 $a 1 online resource (170 pages)
336 $a text $b txt $2 rdacontent
337 $a computer $b c $2 rdamedia
338 $a online resource $b cr $2 rdacarrier
500 $a Source: Dissertation Abstracts International, Volume: 78-11(E), Section: B.
500 $a Adviser: Naresh S. Dalal.
502 $a Thesis (Ph.D.)--The Florida State University, 2017.
504 $a Includes bibliographical references
520 $a Spin-polarized unrestricted density functional theory is used to calculate the molecular properties of magnetic semiconductor quantum dots doped with 3d-metal atoms. We calculate total energies of the low spin antiferromagnetically coupled states using a spin-flipping algorithm leading to the broken-symmetry states. Given the novel nature of the materials studied, we simulate experimental observables such as hyperfine couplings, ionization/ energies, electron affinities, first and second order polarizabilities, band gaps and exchange coupling constants. Specifically, we begin our investigation with pure clusters of (CdSe )16 and demonstrate the dependence of molecular observables on geometrical structures. We also show that the many isomers of this cluster are energetically quite closely spaced, and thus it would be necessary to employ a battery of tests to experimentally distinguish them. Next, we discuss Mn-doping into the cage (CdSe)9 cluster as well as the zinc-blende stacking type cluster (CdSe)36. We show that the local exchange coupling mechanism is ligand-mediated superexchange and simulate the isotropic hyperfine constants. Finally, we discuss a novel study where (CdSe)9 is doped with Mn or Fe up to a full replacement of all the Cd's and discuss the transition points for the magnetic behavior and specifically the greatly differing band-gap shifts. We also outline an unexpected pattern in the polarizability of the material as metals are added and compare our results with the results from theoretical studies of the bulk material.
533 $a Electronic reproduction. $b Ann Arbor, Mich. : $c ProQuest, $d 2018
538 $a Mode of access: World Wide Web
650 4 $a Chemistry. $3 593913
650 4 $a Materials science. $3 557839
650 4 $a Physics. $3 564049
655 7 $a Electronic books. $2 local $3 554714
690 $a 0485
690 $a 0794
690 $a 0605
710 2 $a ProQuest Information and Learning Co. $3 1178819
710 2 $a The Florida State University. $b Chemistry and Biochemistry. $3 1187195
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=10261223 $z click for full text (PQDT)