Roald Hoffmann Quotes

Much of my work in biology has been driven by my early training in chemistry. When studying a new chemical compound, the first and most important thing is to determine its detailed molecular structure.

It does not seem, however, that organic chemists were much worried about barriers to rotation in organic molecules in general at that time because there was no technique available to demonstrate the phenomenon experimentally.

The essential principles of the three-dimensional structure of organic molecules had been correctly formulated by the first Nobel laureate in Chemistry, Jacobus van't Hoff, as early as 1874.

I have lived much of my life among molecules. They are good company. I tell my students to try to know molecules, so well that when they have some question involving molecules, they can ask themselves, What would I do if I were that molecule? I tell them, Try to feel like a molecule; and if you work hard, who knows? Some day you may get to feel like a big molecule!

It turns out all molecular and biological systems have speeds of the atoms move inside them; the fastest possible speeds are determined by their molecular vibrations, and this speed is about a kilometre per second.

The detailed geometry of the coenzyme molecule as a whole is fascinating in its complexity.

Molecular chemistry, the chemistry of the covalent bond, is concerned with uncovering and mastering the rules that govern the structures, properties and transformations of molecular species.

The frontier orbital approach was further developed in various directions by my own group and many other scientists, both theoretical and experimental.

Molecules A and B meet, marry, and beget the species. This takes place in one-millionth of a billionth of a second. This is a fundamental process in nature, and the world was looking for a way to be able to see the process. But many brilliant people said it couldn't be done.

This simple idea served to provide information on the geometrical shape of reacting molecules, and I was able to make the role of the frontier orbitals in chemical reactions more distinct through visualization, by drawing their diagrams.

With this in mind, for some twenty years I have set myself as my particular task the experimental investigation of the connexion between change in the structure and change in the spectra of chemical atoms.

I do not want chemistry to degenerate into a religion; I do not want the chemist to believe in the existence of atoms as the Christian believes in the existence of Christ in the communion wafer.

The visible and near-ultraviolet emission spectrum of the CH radical has been known ever since spectra of an ordinary Bunsen burner have been taken.

Even in the world of molecules the civilising influence of modest restraints is a cause for rejoicing.

All theoretical chemistry is really physics; and all theoretical chemists know it.

Knowing without seeing is at the heart of chemistry.

I have always felt that I understood a phenomenon only to the extent that I could visualise it. Much of the charm organic chemical research has for me derives from structural formulae. When reading chemical journals, I look for formulae first.

Physics and those parts of other fields that grow out of physics - chemistry, the structure of big molecules - in those domains, there is a lot of progress. In many other domains, there is very little progress in developing real scientific understanding.

There's nothing colder than chemistry.

Organic compounds exist in which a hydrogen atom, joined to the carbon, acquires acid properties as a result of the proximity of certain functional groupings.

But the nature of my main work in chemistry can be better represented by more than 280 English publications, of which roughly 200 concern the theory of chemical reactions and related subjects.

The more the relationships of the nitrogen-rich substances to the cell nucleus were recognized, the more the question of the arrangement of the nitrogen and carbon atoms in the molecule came to stand out.

Molecular collision dynamics has been a wonderful area of research for all practitioners. This is especially true for those who were following the footsteps of pioneers and leaders of the field twenty years ago.

Chemistry is the melodies you can play on vibrating strings.

I have lived much of my life among molecules. They are good company.