The Hydrogen Bond Donor/Acceptor Plugin calculates the hydrogen bond donor and acceptor properties of the atoms in the molecule. Atomic data and overall hydrogen bond donor and acceptor multiplicity are displayed for the corresponding atoms of the input molecule (or its microspecies at a given pH).
The plugins is also able to calculate the weighted average hydrogen bond donor and acceptor multiplicities taken over the set of microspecies of the input molecule at a given pH. Then it calculates the distribution of their occurrences at a pH range and display it as a chart.
The following window shows the results of such a calculation.
Fig. 1 H Bond Donor/Acceptor result window
Here are the definition of the donor/acceptor count and sites that is used in the plugin:
The following molecule has a Donor count of 2 and 4 Donor sites, because each N donor atom can provide 2 donor H atoms. It also has an Acceptor count of 6 and 6 Acceptor sites, because each N acceptor atom can accept 1 donor atom.
Fig. 2 Example molecule showing the different assigned HBDA features
Different calculation parameters can be set in the H Bond Donor/Acceptor Options window:
Fig. 3 H Bond Donor/Acceptor Options