X-ray crystallographic study of 2,2',2 '',2"',4,4',4 ''.4"',6,6',6 '',6-dodecanitro-1,1' 3'1 '' 3 '',1"'-quaterphenyl (DODECA) has been carried out Nonbonding-interatomic distances of oxygen atoms inside of all the nitro groups are shorter than those corresponding to the intermolecular contact radii lot oxygen. BY means of the DFT B3INP/6-31(d. p) method a difference of 136 kJ mol(-1) between the X-ray and DFT structures of DODECA was found The bearer of the highest initiation reactivity in its molecule in solid phase should be the nitro group at 4"'-position. in contrast to those at 2'- or 2"-positions in its isolated molecule The most reactive nitro group in the DODECA molecule can be well specified by the relationship between net charges on nitro groups and charges on then nitrogen atoms, both of them tor the X-ray structure The (15)N chemical shift. corresponding to this nitro group for the initiation by impact and shock. correlates very well with these shifts of the reaction centers of the other six "genuine" polynitro arenes.