Molecular orbital theory was seen as a competitor to valence bond theory in the 1930s, before it was realized that the two methods are closely related and that when extended they become equivalent.
Na molekularno orbitalnu teoriju se gledalo kao kompetitora teorije valence veze tokom tridesetih, pre nego što je postalo jasno da su dva metoda blisko srodna i da uz dopunu postaju ekvivalentni.