The interaction between neutral atoms and homopolar bonds according to quantum mechanics is discussed by W. Heitler and F. London. The paper highlights the quantum mechanical ambiguity in the force interactions between neutral atoms, which can explain various observed behaviors, such as homopolar bonding or elastic reflection in hydrogen, and the latter in noble gases. The Pauli principle is also applied here to systems of multiple atoms. The interaction between neutral atoms has been challenging to treat theoretically. While the forces between ions were well understood, the behavior of neutral atoms, especially the possibility of non-polar bonding, was difficult to explain without artificial explanations. The development of quantum mechanics has provided new perspectives for these problems. The charge distribution in new models is different from the Bohr models, leading to different force interactions between neutral atoms. A key quantum mechanical phenomenon, similar to Heisenberg's resonance oscillations, is essential for understanding possible behaviors between neutral atoms. The paper studies the interaction between two hydrogen atoms (Section 1) and two helium atoms (Section 3). It predicts two solutions for the interaction energy: one that shows attraction at intermediate distances and repulsion at small distances, suitable for homopolar molecular formation, and another that shows attraction everywhere, corresponding to van der Waals forces. The first solution is not allowed for helium due to the Pauli exclusion principle, while the second applies to helium alone. The paper presents the wave equation for the two-hydrogen atom problem and discusses the eigenfunctions of the hydrogen ground state.The interaction between neutral atoms and homopolar bonds according to quantum mechanics is discussed by W. Heitler and F. London. The paper highlights the quantum mechanical ambiguity in the force interactions between neutral atoms, which can explain various observed behaviors, such as homopolar bonding or elastic reflection in hydrogen, and the latter in noble gases. The Pauli principle is also applied here to systems of multiple atoms. The interaction between neutral atoms has been challenging to treat theoretically. While the forces between ions were well understood, the behavior of neutral atoms, especially the possibility of non-polar bonding, was difficult to explain without artificial explanations. The development of quantum mechanics has provided new perspectives for these problems. The charge distribution in new models is different from the Bohr models, leading to different force interactions between neutral atoms. A key quantum mechanical phenomenon, similar to Heisenberg's resonance oscillations, is essential for understanding possible behaviors between neutral atoms. The paper studies the interaction between two hydrogen atoms (Section 1) and two helium atoms (Section 3). It predicts two solutions for the interaction energy: one that shows attraction at intermediate distances and repulsion at small distances, suitable for homopolar molecular formation, and another that shows attraction everywhere, corresponding to van der Waals forces. The first solution is not allowed for helium due to the Pauli exclusion principle, while the second applies to helium alone. The paper presents the wave equation for the two-hydrogen atom problem and discusses the eigenfunctions of the hydrogen ground state.