Fig. 1. (a) The calculated ELF for DOTA. The 2D projection through the core and metallic ion of each complex follows: (b) Gd–DOTA, (c) 213Bi–DOTA, (d) 217At–DOTA, (e) 221Fr–DOTA, (f) 225Ac–DOTA. The value of 1 (red) corresponds to the highest probability of electron distribution, the value of 0.5 (green) can be interpreted as an “electron gas” and the value of 0 (blue) indicates no electron distribution. The chelator H, C, N, O atoms are in the same positions for all DOTA complexes and they are shown for Gd–DOTA only. The ELF isosurface level is 0.741.
