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Abstract: We investigate the structural and electronic properties of the single-side fluorinated graphene C4F supercell under equibiaxial strains via first-principles calculations. The results show that, the fluorinated and non-fluorinated C atoms (CA and CB) have two C–C bonds (CA–CB and CB–CB) whose lengths decrease (increase) with increasing equibiaxial compressive (tensile) strain. Due to adsorption of F on CA, the bond angle of three adjacent C atoms CB–CA–CB is always smaller than CA–CB–CB under the same strain. The unstrained C4F supercell exhibits a direct band gap and undergoes the direct-to-indirect transition by applying equibiaxial compressive strains. While the band gap of C4F supercell increases slightly with the increasing equibiaxial tensile strain. [Copyright &y& Elsevier]

An easy synthetic route to N-dichloroacetyl-3,4-dihydro-2 H-1,4-benzoxazine derivatives 3 involves cyclization of 2-aminophenols 1 with 1,2-dibromoethane and subsequent acylation of the resultant 3,4-dihydro-2 H-1,4-benzoxazine derivatives 2 with dichloroacetyl chloride. All compounds were characterized by IR, 1H NMR, 13C NMR, ESI-MS and elemental analysis. The structure of 3a was determined by X-ray crystallographic analysis. [ABSTRACT FROM AUTHOR]

We investigate mechanical, structural and electronic properties of CO2 adsorbed graphitic carbon nitride (g-C3N4) system under biaxial tensile strain via first-principles calculations. The results show that the stress of CO2 adsorbed g-C3N4 system increases and then decreases linearly with the increasing biaxial strain, reaching maximum at 0.12 strain. This is primarily caused by the plane N–C stretching of the g-C3N4. Furthermore, both the Perdew-Burke-Ernzerhof (PBE) and Heyd- Scuseria-Ernzerhof screened hybrid functional (HSE06) band gaps show direct-indirect transitions under biaxial tensile strain and have the maximum also at 0.12 strain. It is found that there is large dipole transition matrix element around Γ point, leading high optical absorption coefficients of the deformed adsorption system, which would be of great use for the applications of new elastic nanoelectronic and optoelectronic devices. [ABSTRACT FROM AUTHOR]