Steric effects arise from the fact that each atom within a molecule occupies a certain amount of space. If atoms are brought too close together, there is an associated cost in energy due to overlapping electron clouds (Pauli or Born repulsion), and this may affect the molecule's preferred shape (conformation) and reactivity.
Famous quotes containing the word effects:
“If one judges love according to the greatest part of the effects it produces, it would appear to resemble rather hatred than kindness.”
—François, Duc De La Rochefoucauld (16131680)