æz ɐpɹˈoʊtʃᵻz stˌoʊɪkɪˈɑːmətɹi, ɪɾ ɐdˈɑːpts ɐ dɪstˈɔːɹɾᵻd bˈɑːdisˈɛntɚd tˈɛtɹɐɡənəl stɹˈʌktʃɚ, tˈɜːmd ðɪ ˈɛpsɪlˌɑːnfˈɔːɹm wɪð ɐn ˈæksɪəl ɹˈeɪʃɪˌoʊ ʌv lˈɛs ðɐn wˈʌn.
As  approaches stoichiometry, it adopts a distorted body-centered tetragonal structure, termed the ε-form with an axial ratio of less than 1.