11951

10964

كارشناسي ارشد

ماده چگال (محاسباتي)

اصفهان: دانشگاه صنعتي اصفهان، دانشكده فيزيك

1395

نه، 94ص.: مصور، جدول، نمودار

ص. ع. به فارسي و انگليسي

هادي اكبرزاده

جواد هاشمي فر

مجتبي اعلايي، اسماعيل عبدالحسيني سارسري

1395/09/30

كتابنامه

فيزيك

فيزيك

ID10964

Study of the electronic properties and absorption spectrum ofisomers of MoSe2 nanoclusters by using evolutionary algorithm and Density Functional Theory Zohreh Hashemi z hashemi@ph iut ac ir 15 11 2016 Department of physics Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisor Prof H Akbarzadeh akbarzad@cc iut ac irABSTRACTTransition metal dichalcogenides TMDs MX2 M W Mo X S Se Te encompass alarge class of two dimensional layered materials graphene like which have numerousapplications in fields such as catalysis energy storage dry lubrication microelectronicsand optoelectronics Like graphite TMDC bulk crystals are formed of monolayers boundto each other by Van der Waals attraction In each monolayer atoms sticks together withCovalent bonds additionally a transition from indirect bandgap 1 1eV in the bulk limit todirect bandgap 1 5eV in the quantum 2D limit exists Since the discovery of graphene two dimensional Nano structures have attracted lots of interests in nano science andcondensed matter physics In Nano size TMDC is very useful for hydrogen evolutionreaction HER catalyst So far no Comprehensive research on MoSe2 Nano materials has appear in literally Nanostructure or nanocluster are often quite different from bulk and could have interestingproperties but these are yet to be well understood Here we present search structure resultson stoichiometric MoSe2 n n 1 10 clusters and report the electronic and optical properties For search structure we employ USPEX code which is based on evolutionary algorithm This code unable to relax structures and can just produce them For relaxation we use offull potential density functional theory DFT approach by FHI aims code within fourdifferent exchange correlation functional The electronic properties and energy gap of the lowest energy isomers were computedwithin several schemes including semi local PBE and BLYP functional hybrid B3LYP PBE0 functional many body based DFT GW approach and fundamental gapcalculations Vibrational spectra of the lowest lying isomers computed by the forceconstant method are used to address IR spectra of the clusters At the end we investigatethe temperature effect by using Helmholtz free energy definition Keywords MoSe2 Nanoclusters Density Functional Theory DFT FHI aims USPEX

هادي اكبرزاده

جواد هاشمي فر

مجتبي اعلايي، اسماعيل عبدالحسيني سارسري