T The calculations of quantum mechanical descriptors of 79 heterogeneous phenol compounds were presented at the HF/6-31G* and B3LYP/6-31G* levels of theory.Quantitative structure-activity relationship(QSAR)models of the growth inhibition activity(pIGC50)of 79 heterogeneous phenols were established using some of the following calculated quantum mechanical descriptors:the zero point energy(ZPE),the front-line orbital energy(EHOMO,ELUMO),the differences between HOMO and LUMO energies(△E),and the molecular dipole moment(μ).The QSAR models obtained by employing multiple linear regression techniques are aimed at correlating the structures to their experimental pIGC50.The most significant is a one-parameter linear equation with the correlation coefficient R2 values to be 0.855(HF)and 0.844(B3LYP).The results display that the zero point energy as a special quantum-chemical descriptor in the QSAR equations indicates the existence of Casimir force in the interaction between the molecules of compounds and biological receptor(cells).The physical mechanism of structure-activity of the molecules at a deeper level would have a new understanding.