Abstract
Diamondiynes, a new class of diamond-like carbon allotropes composed of carbon with sp/sp(3)-hybridized carbon networks, exhibit unique structural motifs that have not been previously reported in carbon materials. These architectures feature sublattices that are both interlocked and capable of relative movement. Using the density functional theory approach with semilocal and hybrid exchange-correlation functionals, we have conducted an extensive investigation into the structural and electronic properties of five diamondyne structures. Our results show that diamondiynes are thermodynamically stable and exhibit wide electronic band gaps, ranging from 2.2 to 4.0 eV. They are flexible yet highly resistant compared to other diamond-like structures. They have relatively small cohesive energy values, consistent with the fact that one diamondyne structure (2f-unsym) has already been experimentally realized. Our results provide new physical insights into diamond-like carbon networks and suggest promising directions for the development of porous, tunable frameworks with potential applications in energy storage and conversion.