According to the book I'm referring to ("S.M. Sze Semiconductor Devices"), gallium has an oxidation state of +1 and arsenic has that of -1. This should not be possible as each of these elements forms a covalent bond with four atoms of the other element (structure of GaAs semiconductor). For that to be possible, shouldn't both of them have one electron in $\ce{3s}$ subshell and three electrons in $\ce{3p}$ subshell?

  • $\begingroup$ Which book? And how meaningful are these oxidation states anyway? $\endgroup$ – Oscar Lanzi Jun 30 '18 at 11:24
  • $\begingroup$ Oxidation states are meaningful because they tell about the electronic configuration that might have existed during bonding $\endgroup$ – Goyal Jun 30 '18 at 14:38
  • $\begingroup$ @OscarLanzi The book I'm referring to is S.M. Sze Semiconductor Devices $\endgroup$ – Goyal Jul 1 '18 at 3:39

In general, gallium can have +1 and +3 oxidation states, though +1 is a very rare condition. In its turn arsenic possible oxidation states are -3, +3 and +5. As it is stated in Wikipedia, gallium oxidation state in gallium arsenide is +3. Once again, arsenic has -3 oxidation state in arsenides or intermetallic compounds. Therefore, gallium arsenide oxidation states are +3 for Ga and -3 for As. This is logical because the electronegativity of As is higher then Ga. As for Simon Sze, he is an electrical engineer and physicist and not a chemist. From the mathematical point of view (-3)(+3) is the same thing as (-1)(+1).

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.