. Author manuscript; available in PMC: 2017 Aug 24.

Published in final edited form as: J Comput Aided Mol Des. 2016 Aug 24;30(8):595–608. doi: 10.1007/s10822-016-9938-8

Table 2.

Atom features

Feature	Description	Size
Atom type^a	H, C, N, O, F, P, S, Cl, Br, I, or metal (one-hot or null)	11
Chirality	R or S (one-hot or null)	2
Formal charge	Integer electronic charge	1
Partial charge	Calculated partial charge	1
Ring sizes	For each ring size (3–8), the number of rings that include this atom	6
Hybridization	sp, sp², or sp³ (one-hot or null)	3
Hydrogen bonding	Whether this atom is a hydrogen bond donor and/or acceptor (binary values)	2
Aromaticity	Whether this atom is part of an aromatic system	1
		27

Included in the “simple” featurization (see “Input featurization” section)