Nickel(II) and zinc(II) complexes with N-(5,6-dihydro-4H-1,3-thiazin-2-yl)-2-aminobenzimidazole (BzTz): Synthesis, spectral and structural characterization

Application of the charge flipping algorithm to the ab initio structure determination of disordered ZnCl2(BzTz)2 [BzTz = N-(5,6-dihydro-4H-1,3-thiazin-2-yl)-2-aminobenzimidazole]

“…The molecules within the crystal are bonded by van der Waals forces, being the shortest distance between adjacent molecules through non-H atoms of 3.167(11) Å . Additional details can be found elsewhere [14]. From the viewpoint of this work, the most important feature of the ZnCl 2 (BzTz) 2 system is the existence of positional disorder in the thiazine rings, affecting the C(3), C (13), and N(5) atoms.…”

“…This d value is significantly higher than those typically reported for charge flipping [8]; the reason for such a choice is that lower values, despite led to convergence, did not allow to identify all the atoms in the structure. Table 1; reference atomic positions calculated by direct methods elsewhere [14] are also included for comparison. The agreement between both solutions is notorious.…”

“…The spots correspond to the charge distribution map calculated by charge flipping. The solid spheres represent the individual atoms, whose positions have been calculated from direct methods [14] identified ones. For instance, Fig.…”

“…Details of the preparation and structure determination by direct methods of the complex ZnCl 2 (BzTz) 2 [BzTz = N-(5,6-dihydro-4H-1,3-thiazin-2-yl)-2-aminobenzimidazole] are given elsewhere [14]. The empirical formula is C 22 Cl 2 N 8 S 2 Zn.…”

“…Atomic positions (x, y, z) calculated by charge flipping and reference ones (x 0 , y 0 , z 0 ) calculated by direct methods[14] for ZnCl 2 (BzTz)2 …”