The structure and electronic properties of single-layered carbon nitride graphenes are examined computationally with hybrid-exchange functionals in periodic density functional theory calculations. Unlike pure carbon graphene that provides a metallic nanomaterial, carbon nitride graphenes form semiconductors with band gaps ranging up to 5 eV. The band gap is sensitive to external perturbations that can be introduced chemically by adatom adsorption or physically by constraining the lattice parameter. Carbon nitride graphenes could possibly pave the way for a new range of smaller and faster transistors, as well as have useful sensing and actuating properties.

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The compression of the layered carbon nitride C6N9H3·HCl was studied experimentally and with density functional theory (DFT) methods. This material has a polytriazine imide structure with Cl− ions contained within C12N12 voids in the layers. The data indicate the onset of layer buckling accompanied by movement of the Cl− ions out of the planes beginning above 10–20 GPa followed by an abrupt change in the diffraction pattern and c axis spacing associated with formation of a new interlayer bonded phase. The transition pressure is calculated to be 47 GPa for the ideal structures. The new material has mixed sp2–sp3 hybridization among the C and N atoms and it provides the first example of a pillared-layered carbon nitride material that combines the functional properties of the graphitic-like form with improved mechanical strength. Similar behavior is predicted to occur for Cl-free structures at lower pressures.

The synthesis and crystal structure of a novel layered aluminophosphate is described. The structure was solved from single-crystal X-ray diffraction data and confirmed by high-resolution powder diffraction and computational studies. The as-synthesized layered material, with composition [AlPO4(OH)](NH3C2H4C6H5), crystallizes in the monoclinic space group C2/c with a = 39.06(10) Å, b = 5.31(13) Å, c = 9.67(2) Å, α = 90°, β = 94.6(4)°, and γ = 90°. In the aluminophosphate layers, the six-coordinated aluminum polyhedra form infinite chains that are cross-linked by phosphate groups. These inorganic layers are stabilized via strong hydrogen bonding to the protonated organic templates, involving the terminal oxygen atoms of the phosphate groups. Using quantum mechanical (QM) and interatomic potential (IP) techniques, we established the location of the protons in the layer and the structure's stability.

We report the synthesis of different heteroatom-substituted aluminophosphates with AFI and ATS topology and their ability to store toluene in wet and dry conditions. By mixing Zeolite A with the material to be tested, it was possible to obtain identical results in both wet and dry conditions. Molecular dynamics simulations coupled with high-resolution X-ray powder diffraction studies allowed us to obtain detailed information on the toluene-framework interactions.