The concept of molecular structure is fundamental to the practice and understanding of chemistry, but the meaning of this term has evolved and is still evolving. The Born–Oppenheimer separation of electronic and nuclear motions lies at the heart of most modern quantum chemical models of molecular structure. While this separation introduces a great computational and practical simplification, it is neither essential to the conceptual formulation of molecular structure nor universally valid. Going beyond the Born–Oppenheimer approximation introduces new paradigms, bringing fresh (...) insight into the chemistry of fluxional molecules, proteins, superconductors and macroscopic dielectrics, thus opening up new avenues for exploration. But it requires that our ideas of molecular structure need to evolve beyond simple ball-and-stick-type models. (shrink)

Me circunscribo a la química, en cuanto ciencia empírica natural. Aquélla comprende el mundo como totalidad de fenómenos químicos y abstrae de estos los objetos químicos. Examino los confines de la química, entendidos como límites estructurales, cognitivos y a priori. Ahora bien, la investigación química se realiza en campos de experimentación observacional, donde interactúan el observador químico, el lenguaje científico de la química, los sensores químicos y los fenómenos químicos. Por lo tanto, examino los confines de cada uno de estos (...) factores. I restrict myself to Chemistry, as a natural empirical science. That one understands the world as a totality of chemical phenomena and it abstracts from these one the chemical objects. I examine the boundaries of Chemistry, as structural, cognitive and a priori limits. Now then, chemical research takes place as observation-experimentation fields, where chemical observer, scientific language of Chemistry, chemical sensors and phenomena interact. Therefore, I examine the boundaries of everyone of these factors. (shrink)