Abstract
We present a tight-binding molecular-dynamics investigation on the structural, elastic and electronic properties of the smallest periodic tetrahedral carbon schwarzites fcc-(C28)2, fcc-(C36)2 and fcc-(C40)2. Although their unit cells are equivalent to the fullerenes C20, C28 and C32, respectively, their stability is found to be much higher. Moreover they present alternatively metallic or insulating character, which would make this class of hypothetical materials suitable to a wide range of applications.