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Table 1 Descriptors in the constitutional descriptors (CD) key

From: A generalizable definition of chemical similarity for read-across

Name Description
MW Molecular weight
AMW Average molecular weight
Sv Sum of atomic van der Waals volumes
Mv Mean atomic van der Waals volum
Sp Sum of atomic polarizabilities
Mp Mean atomic polarizability
Se Sum of atomic Sanderson electronegativities
Me Mean atomic Sanderson electronegativity
nAt Number of atoms
nSk Number of non-H atoms
nBt Number of bonds
nBo Number of non-H bonds
nBm Number of multiple bonds
nDblBo Number of double bonds
nTrpBo Number of triple bonds
nArBo Number of aromatic bonds
SCBO Sum of conventional bond orders (H-depleted)
nH Number of Hydrogen atoms
nC Number of Carbon atoms
nN Number of Nitrogen atoms
nO Number of Oxygen atoms
nP Number of Phosphorous atoms
nS Number of Sulfur atoms
nF Number of Fluorine atoms
nCl Number of Chlorine atoms
nBr Number of Bromine atoms
nI Number of Iodine atoms
nB Number of Boron atoms
HPerc Percentage of H atoms
CPerc Percentage of C atoms
NPerc Percentage of N atoms
OPerc Percentage of O atoms
XPerc Percentage of halogen atoms
nHet Number of heteroatoms
nX Number of halogen atoms