Formation mechanism and properties of CdS-Ag2S nanorod superlattices.
The mechanism of formation of recently fabricated CdS-Ag(2)S nanorod superlattices is considered and their elastic properties are predicted theoretically based on experimental structural data. We consider different possible mechanisms for the spontaneous ordering observed in these 1D nanostructures, such as diffusion-limited growth and ordering due to epitaxial strain. A simplified model suggests that diffusion-limited growth partially contributes to the observed ordering, but cannot account for the full extent of the ordering alone. The elastic properties of bulk Ag(2)S are predicted using a first principles method and are fed into a classical valence force field (VFF) model of the nanostructure. The VFF results show significant repulsion between Ag(2)S segments, strongly suggesting that the interplay between the chemical interface energy and strain due to the lattice mismatch between the two materials drives the spontaneous pattern formation.
Demchenko
Denis O
DO
Computational Research Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA. dodemchenko@lbl.gov
Robinson
Richard D
RD
Sadtler
Bryce
B
Erdonmez
Can K
CK
Alivisatos
A Paul
AP
Wang
Lin-Wang
LW
D019187:Cadmium Compounds / Q000737:chemistry*; D003198:Computer Simulation; D003460:Crystallization / Q000379:methods*; D055119:Elastic Modulus; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D036103:Nanotechnology / Q000379:methods; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D018036:Selenium Compounds / Q000737:chemistry*; D018030:Silver Compounds / Q000737:chemistry*; D013499:Surface Properties
D019187:Cadmium Compounds; D046911:Macromolecular Substances; D018036:Selenium Compounds; D018030:Silver Compounds; C013251:silver sulfide; C058667:cadmium selenide