Siegbahn, K., Nordling, C., Fahlman, A., Nordberg, R., Hamrin, K., Carlsson, R., Hedman, J., Ericson, U., Axelson, G., Bergmark, T., Lindgren, I., and Karlsson, S. E ...

Bond breaking is an endothermic process. The opposite is true if we want to make new bonds. Energy is released when new chemical bonds are formed, so bond making is an exothermic process.

It is true that we know little in regard to what we symbolise by a shared pair of electrons, but even less was ever known of the inner meaning of the single bond of organic chemistry, although ...