Related Experiment Video
Updated: Mar 6, 2026

Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
Periodicity of band gaps of chiral α-graphyne nanotubes
Baotao Kang1, Daeheum Cho2, Jin Yong Lee2
1School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China. chm_kangbt@ujn.edu.cn.
Abstract:
Electronic structures of zigzag (n,0), armchair (n,n), and chiral (n,m) α-graphyne nanotubes (αGNTs) with n = 2-7 were investigated using density functional tight binding calculations. Oscillatory behavior of the band gaps with a period of every (n - m) = 3 was found for each tube. According to the periodicity, αGNTs could be classified into three families, and their band gaps were in the increasing order of (n - m) = 3a < 3a + 1 < 3a + 2. Among the three families, αGNTs with (n - m) = 3a became effectively semimetallic when the tube size was larger than approximately 2 nm, while the other families remained semiconducting.
Related Concept Videos
IR Frequency Region: Alkyne and Nitrile Stretching
Comparing the stretching vibrational frequency of C≡C triple bonds with that of double and single bonds, it is evident that C≡C triple bonds exhibit a higher stretching frequency than C=C double and C–C single bonds. Similarly, the C≡N triple bond...
IR Spectrum Peak Splitting: Symmetric vs Asymmetric Vibrations
IR Frequency Region: X–H Stretching
¹H NMR of Conformationally Flexible Molecules: Variable-Temperature NMR
Prochirality
IR Absorption Frequency: Hybridization
Among the sp, sp2, and sp3 hybridized orbitals, sp orbitals have the maximum s character (50%). Consequently, the electrons are held more closely to the nucleus, resulting in stronger and shorter C–H bonds that...

