An analysis of the mechanical behavior of new tetragonal carbon allotropes has been carried out by calculating the elastic properties by inducing finite distortions of the lattice. The allotropes are fully described by the calculated sets of elastic constants C ij given in Table . All C ij values are positive, indicating mechanically stable phases. The major (i.e., C 11 and C 33 ) C ij values of C 5 are systematically larger than those of C 6 and C 7 . The analysis of the elastic tensors was performed using the ELATE software , which provides the bulk (B), shear (G) and Young's (E) moduli, and the Poisson's ratio () along different averaging methods; in the present work, the Voigt approach was chosen. Table shows the calculated elastic moduli, with values that follow the trends observed for C ij .