Publication
Title
Electronic and vibrational properties of $PbI_{2}$ : from bulk to monolayer
Author
Abstract
 Using first-principles calculations, we study the dependence of the electronic and vibrational properties of multilayered PbI2 crystals on the number of layers and focus on the electronic-band structure and the Raman spectrum. Electronic-band structure calculations reveal that the direct or indirect semiconducting behavior of PbI2 is strongly influenced by the number of layers. We find that at 3L thickness there is a direct-to-indirect band gap transition (from bulk-to-monolayer). It is shown that in the Raman spectrum two prominent peaks, A(1g) and E-g, exhibit phonon hardening with an increasing number of layers due to the interlayer van der Waals interaction. Moreover, the Raman activity of the A(1g) mode significantly increases with an increasing number of layers due to the enhanced out-of-plane dielectric constant in the few-layer case. We further characterize rigid-layer vibrations of low-frequency interlayer shear (C) and breathing (LB) modes in few-layer PbI2. A reduced monatomic (linear) chain model (LCM) provides a fairly accurate picture of the number of layers dependence of the low-frequency modes and it is shown also to be a powerful tool to study the interlayer coupling strength in layered PbI2.
Language
English
Source (journal)
Physical review B / American Physical Society. - New York, N.Y, 2016, currens
Publication
New York, N.Y : American Physical Society , 2018
ISSN
2469-9969 [online]
2469-9950 [print]
Volume/pages
98 :8 (2018) , 11 p.
Article Reference
085431
ISI
000442667200008
Medium
E-only publicatie
Full text (Publisher's DOI)
Full text (open access)
UAntwerpen
 Faculty/Department Research group Project info Theoretical investigation of electronic transport in functionalized 2D transition metal dichalcogenides (Trans2DTMD). Publication type Subject Affiliation Publications with a UAntwerp address