Winkler, B., C. J. Pickard, et al. (1999). "Prediction of a nanoporous sp2-carbon framework structure by combining graph theory with quantum mechanics." Chemical Physics Letters 312(5-6): 536-541.

A nanoporous carbon framework structure is predicted by combining graph theoretical approaches and density functional calculations. Bond lengths in this polymorph, with all atoms sp(2)-hybridised, are in good agreement with typical C-C and C=C bond lengths, bond angles are close to 120 degrees, and it is 0.36 eV/atom less stable than diamond. The electronic structure suggests it is a quasi-one-dimensional metal with anisotropic electronic properties and a spectroscopic signature. The compound has a high bulk modulus of 234(1) GPa but a density similar to that of graphite and amorphous carbon. Changes in the lattice parameters on compression are strongly anisotropic.

http://dx.doi.org/10.1016/s0009-2614(99)00943-4