citation of value from [S89b] for alumina !!, there ionic strength varied between 0.0001 and 1.0 M NaCl or CsCl; [S89b]: from log K=7.5 with pK1=6 follows for eq. 2 logKint=1.5 , pKint -1.5 reference for background electrolyte (used for anatase!) (error in table 1 with pH=1.5)! »Ti-OH2<1+> + Cl<1-> = »Ti-OH2-Cl logK = 1.5 »Ti-OH + H<1+> = »Ti-OH2<1+> -pK1 = logK = 3.5 sum »Ti-OH + Cl<1->+ H<1+> = »Ti-OH2-Cl logK= 1.5+3.5 = 4.0