The classical Lewis–Langmuir electron pair model remains central to chemical bonding theories despite its inherent contradictions with quantum mechanical principles such as antisymmetry. This paper revisits the long-forgotten Linnett’s double quartet (LDQ) model, which integrates spin considerations into chemical bonding. We demonstrate that the distribution of electrons at the maxima of the square of the wave function (Born maxima) highlights the rigidity of the same-spin electron blocks and validates the LDQ framework in atoms and molecules. A generalized LDQ model accounts for all bond types, including covalent, polar covalent, ionic, dative, and electron-deficient, and directly incorporates electron correlation effects, providing a rigorous yet intuitive approach to bonding. This perspective also reveals fundamental flaws in conventional mean-field descriptions that ignore the correlated motion of electrons. By bridging traditional and quantum paradigms, the generalized LDQ model offers a robust tool for understanding chemical bonding, with implications for education, experimental design, and theoretical advancements.

A society dedicated to advancing the science and research of chemical bonding theory in Europe. Founded with the aim of fostering scientific excellence and collaboration, ECCB serves as a hub for researchers, academics, and professionals in the field. Our activities include organizing conferences such as the European Symposium on Chemical Bonding (ESCB), awarding prizes and scholarships for groundbreaking research, and publishing special issues in scientific journals to highlight significant contributions in chemical bonding. Committed to non-profit and public-benefit principles, ECCB ensures that all funds are utilized solely for promoting scientific endeavors without personal gain. With its headquarters in Leipzig, ECCB is a vibrant community that welcomes members from across Europe, offering opportunities for professional growth, networking, and recognition in the field of chemical bonding theory.