DFT investigations on M-BCP8 (M = Zn, Ni) bridled chiral porphyrins. Analysis of conformational stability. Demonstration of atropoisomer stability depending on the metal ion and environment. Effects of BSSE errors and dimer formation. Thermodynamic entropy and ZPE parameters that can possibly influence the αβαβ/αααα equilibriums. Validation of DFT techniques.