O=c1c2cc(S(=O)(=O)O)ccc2nc(COc2ccc(Oc3ccc(Cl)cc3Cl)cc2)n1-c1ccc(Oc2ccc(Cl)cc2)cc1Cl
An acid's negative base-10 logarithmic dissociation constant (pKa) follows directly from its underlying thermodynamics; the negative pKa is directly proportional to its standard Gibbs free energy change. What is the negative pKa value of this molecule?