Van-der-Waals radii are taken from:
http://www.ccdc.cam.ac.uk/products/csd/radii/
[...]
atom radius/au charge
1 c 4.497548 -0.621028
2 h 3.174740 0.155281
[...]
Way | q(Carbon) | q(Hydrogen) |
just $esp_fit kollman | -0.621 | 0.155 |
with explicitly giving default radii1 | -0.621 | 0.155 |
with radii of the cited table2 | -0.684 | 0.171 |