DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Real-space pseudopotential study of vibrational properties and Raman spectra in Si–Ge core-shell nanocrystals

Abstract

We examine the vibrational properties and Raman spectra of Si–Ge core-shell nanostructures using real-space pseudopotentials constructed within density functional theory. Our method uses no empirical parameters, unlike many popular methods for predicting Raman spectra for nanocrystals. Here, we find the dominant features of the Raman spectrum for the Si–Ge core-shell structure to be a superposition of the Raman spectra of the Ge and Si nanocrystals with optical peaks around 300 and 500 cm-1, respectively. We also find a Si–Ge “interface” peak at 400 cm-1. The Ge shell causes the Si core to expand from the equilibrium structure. This strain induces significant redshift in the Si contribution to the vibrational and Raman spectra, while the Ge shell is largely unstrained and does not exhibit this shift. We find that the ratio of peak heights is strongly related to the relative size of the core and shell regions. This finding suggests that Raman spectroscopy may be used to characterize the size of the core and shell in these structures.

Authors:
 [1];  [2]
  1. Univ. of Texas, Austin, TX (United States). Dept. of Chemical Engineering
  2. Univ. of Texas, Austin, TX (United States). Dept. of Physics and Chemical Engineering, Center for Computational Materials, Inst. for Computational Engineering and Sciences
Publication Date:
Research Org.:
Univ. of Texas, Austin, TX (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR). Scientific Discovery through Advanced Computing (SciDAC); USDOE Office of Science (SC), Basic Energy Sciences (BES)
OSTI Identifier:
1468776
Alternate Identifier(s):
OSTI ID: 1243362
Grant/Contract Number:  
SC0008877; FG02-06ER46286
Resource Type:
Accepted Manuscript
Journal Name:
Journal of Chemical Physics
Additional Journal Information:
Journal Volume: 144; Journal Issue: 12; Journal ID: ISSN 0021-9606
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 36 MATERIALS SCIENCE

Citation Formats

Bobbitt, N. Scott, and Chelikowsky, James R. Real-space pseudopotential study of vibrational properties and Raman spectra in Si–Ge core-shell nanocrystals. United States: N. p., 2016. Web. doi:10.1063/1.4943970.
Bobbitt, N. Scott, & Chelikowsky, James R. Real-space pseudopotential study of vibrational properties and Raman spectra in Si–Ge core-shell nanocrystals. United States. https://doi.org/10.1063/1.4943970
Bobbitt, N. Scott, and Chelikowsky, James R. Fri . "Real-space pseudopotential study of vibrational properties and Raman spectra in Si–Ge core-shell nanocrystals". United States. https://doi.org/10.1063/1.4943970. https://www.osti.gov/servlets/purl/1468776.
@article{osti_1468776,
title = {Real-space pseudopotential study of vibrational properties and Raman spectra in Si–Ge core-shell nanocrystals},
author = {Bobbitt, N. Scott and Chelikowsky, James R.},
abstractNote = {We examine the vibrational properties and Raman spectra of Si–Ge core-shell nanostructures using real-space pseudopotentials constructed within density functional theory. Our method uses no empirical parameters, unlike many popular methods for predicting Raman spectra for nanocrystals. Here, we find the dominant features of the Raman spectrum for the Si–Ge core-shell structure to be a superposition of the Raman spectra of the Ge and Si nanocrystals with optical peaks around 300 and 500 cm-1, respectively. We also find a Si–Ge “interface” peak at 400 cm-1. The Ge shell causes the Si core to expand from the equilibrium structure. This strain induces significant redshift in the Si contribution to the vibrational and Raman spectra, while the Ge shell is largely unstrained and does not exhibit this shift. We find that the ratio of peak heights is strongly related to the relative size of the core and shell regions. This finding suggests that Raman spectroscopy may be used to characterize the size of the core and shell in these structures.},
doi = {10.1063/1.4943970},
journal = {Journal of Chemical Physics},
number = 12,
volume = 144,
place = {United States},
year = {Fri Mar 25 00:00:00 EDT 2016},
month = {Fri Mar 25 00:00:00 EDT 2016}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 3 works
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

Radial-Position-Controlled Doping in CdS/ZnS Core/Shell Nanocrystals
journal, September 2006

  • Yang, Yongan; Chen, Ou; Angerhofer, Alexander
  • Journal of the American Chemical Society, Vol. 128, Issue 38, p. 12428-12429
  • DOI: 10.1021/ja064818h

Epitaxial core–shell and core–multishell nanowire heterostructures
journal, November 2002

  • Lauhon, Lincoln J.; Gudiksen, Mark S.; Wang, Deli
  • Nature, Vol. 420, Issue 6911, p. 57-61
  • DOI: 10.1038/nature01141

Derivation of equations of state for ideal crystals of simple structure
journal, June 2011


Real space pseudopotential calculations for size trends in Ga- and Al-doped zinc oxide nanocrystals with wurtzite and zincblende structures
journal, September 2014

  • Bobbitt, N. Scott; Sai, Na; Marom, Noa
  • The Journal of Chemical Physics, Vol. 141, Issue 9
  • DOI: 10.1063/1.4893478

Epitaxial Growth of Highly Luminescent CdSe/CdS Core/Shell Nanocrystals with Photostability and Electronic Accessibility
journal, July 1997

  • Peng, Xiaogang; Schlamp, Michael C.; Kadavanich, Andreas V.
  • Journal of the American Chemical Society, Vol. 119, Issue 30, p. 7019-7029
  • DOI: 10.1021/ja970754m

Quantum algorithms for predicting the properties of complex materials
conference, January 2012

  • Schofield, Grady; Saad, Yousef; Chelikowsky, James R.
  • Proceedings of the 1st Conference of the Extreme Science and Engineering Discovery Environment on Bridging from the eXtreme to the campus and beyond - XSEDE '12
  • DOI: 10.1145/2335755.2335820

The pseudopotential-density functional method applied to nanostructures
journal, March 2000


Probing the phonon confinement in ultrasmall silicon nanocrystals reveals a size-dependent surface energy
journal, April 2011

  • Crowe, Iain F.; Halsall, Matthew P.; Hulko, Oksana
  • Journal of Applied Physics, Vol. 109, Issue 8
  • DOI: 10.1063/1.3575181

The one phonon Raman spectrum in microcrystalline silicon
journal, August 1981


First-principles calculations of lattice-strained core-shell nanocrystals
journal, August 2011


High-Efficiency Silicon Nanocrystal Light-Emitting Devices
journal, May 2011

  • Cheng, Kai-Yuan; Anthony, Rebecca; Kortshagen, Uwe R.
  • Nano Letters, Vol. 11, Issue 5
  • DOI: 10.1021/nl2001692

Efficient Synthesis of Highly Luminescent Copper Indium Sulfide-Based Core/Shell Nanocrystals with Surprisingly Long-Lived Emission
journal, February 2011

  • Li, Liang; Pandey, Anshu; Werder, Donald J.
  • Journal of the American Chemical Society, Vol. 133, Issue 5, p. 1176-1179
  • DOI: 10.1021/ja108261h

First-principles study of vibrational modes and Raman spectra in P-doped Si nanocrystals
journal, May 2014


CdSe/CdS/ZnS and CdSe/ZnSe/ZnS Core−Shell−Shell Nanocrystals
journal, December 2004

  • Talapin, Dmitri V.; Mekis, Ivo; Götzinger, Stephan
  • The Journal of Physical Chemistry B, Vol. 108, Issue 49
  • DOI: 10.1021/jp046481g

Infrared and Raman spectra of disordered materials from first principles
journal, August 2005


Raman Spectroscopy of Oxide-Embedded and Ligand-Stabilized Silicon Nanocrystals
journal, April 2012

  • Hessel, Colin M.; Wei, Junwei; Reid, Dariya
  • The Journal of Physical Chemistry Letters, Vol. 3, Issue 9
  • DOI: 10.1021/jz300309n

Stable Photogenerated Carriers in Magnetic Semiconductor Nanocrystals
journal, March 2006

  • Liu, William K.; Whitaker, Kelly M.; Kittilstved, Kevin R.
  • Journal of the American Chemical Society, Vol. 128, Issue 12
  • DOI: 10.1021/ja060488p

The crystal structural evolution of nano-Si anode caused by lithium insertion and extraction at room temperature
journal, November 2000


Efficient pseudopotentials for plane-wave calculations
journal, January 1991


Increasing Solar Absorption for Photocatalysis with Black Hydrogenated Titanium Dioxide Nanocrystals
journal, January 2011


First-Principles Determination of the Soft Mode in Cubic ZrO 2
journal, May 1997


Tuning the optical and electronic properties of colloidal nanocrystals by lattice strain
journal, December 2008

  • Smith, Andrew M.; Mohs, Aaron M.; Nie, Shuming
  • Nature Nanotechnology, Vol. 4, Issue 1
  • DOI: 10.1038/nnano.2008.360

Controlling Diffusion of Lithium in Silicon Nanostructures
journal, March 2010

  • Chan, Tzu-Liang; Chelikowsky, James R.
  • Nano Letters, Vol. 10, Issue 3
  • DOI: 10.1021/nl903183n

Hybrid Nanorod-Polymer Solar Cells
journal, March 2002

  • Huynh, W. U.; Dittmer, Janke J.; Alivisatos, A. Paul
  • Science, Vol. 295, Issue 5564, p. 2425-2427
  • DOI: 10.1126/science.1069156

Ab initio molecular dynamics simulations using a Chebyshev-filtered subspace iteration technique
journal, August 2010


Quantum Confinement in Phosphorus-Doped Silicon Nanocrystals
journal, January 2004


Self-Purification in Semiconductor Nanocrystals
journal, June 2006


First-principles calculations of Raman spectra in Li-doped Si nanocrystals
journal, February 2016


Silicon nanocluster crystallization in SiOx films studied by Raman scattering
journal, August 2008

  • Hernández, S.; Martínez, A.; Pellegrino, P.
  • Journal of Applied Physics, Vol. 104, Issue 4
  • DOI: 10.1063/1.2968244

Size-Dependent Spintronic Properties of Dilute Magnetic Semiconductor Nanocrystals
journal, June 2005


Raman spectra of c - Si 1 x Ge x alloys
journal, May 1989


Silicon nanostructures for third generation photovoltaic solar cells
journal, July 2006


Semiconductor Nanocrystals as Fluorescent Biological Labels
patent, September 1998


Size Limits on Doping Phosphorus into Silicon Nanocrystals
journal, February 2008

  • Chan, T. -L.; Tiago, Murilo L.; Kaxiras, Efthimios
  • Nano Letters, Vol. 8, Issue 2
  • DOI: 10.1021/nl072997a

Parallel self-consistent-field calculations via Chebyshev-filtered subspace acceleration
journal, December 2006


PARSEC – the pseudopotential algorithm for real-space electronic structure calculations: recent advances and novel applications to nano-structures
journal, April 2006

  • Kronik, Leeor; Makmal, Adi; Tiago, Murilo L.
  • physica status solidi (b), Vol. 243, Issue 5
  • DOI: 10.1002/pssb.200541463

Real space method for the electronic structure of one-dimensional periodic systems
journal, October 2008

  • Han, Jiaxin; Tiago, Murilo L.; Chan, T. -L.
  • The Journal of Chemical Physics, Vol. 129, Issue 14
  • DOI: 10.1063/1.2988316

An Investigation of the Formation and Growth of Oxide-Embedded Silicon Nanocrystals in Hydrogen Silsesquioxane-Derived Nanocomposites
journal, May 2007

  • Hessel, Colin M.; Henderson, Eric J.; Veinot, Jonathan G. C.
  • The Journal of Physical Chemistry C, Vol. 111, Issue 19
  • DOI: 10.1021/jp070908c

Ground State of the Electron Gas by a Stochastic Method
journal, August 1980


Core/Shell Semiconductor Nanocrystals
journal, January 2009


Hole spin relaxation in Ge–Si core–shell nanowire qubits
journal, December 2011

  • Hu, Yongjie; Kuemmeth, Ferdinand; Lieber, Charles M.
  • Nature Nanotechnology, Vol. 7, Issue 1
  • DOI: 10.1038/nnano.2011.234

First-Principles Study of Confinement Effects on the Raman Spectra of Si Nanocrystals
journal, September 2010


A first-principles study of the electronic and structural properties of Sb and F doped SnO2 nanocrystals
journal, January 2015

  • Kim, Minjung; Marom, Noa; Scott Bobbitt, N.
  • The Journal of Chemical Physics, Vol. 142, Issue 4
  • DOI: 10.1063/1.4906150

Space-separated quantum cutting with silicon nanocrystals for photovoltaic applications
journal, January 2008


Si/SiO2 core shell clusters probed by Raman spectroscopy
journal, August 2005


Interfacial Alloying in CdSe/CdS Heteronanocrystals: A Raman Spectroscopy Analysis
journal, December 2011

  • Tschirner, Norman; Lange, Holger; Schliwa, Andrei
  • Chemistry of Materials, Vol. 24, Issue 2
  • DOI: 10.1021/cm202947n