There is a further degree of freedom for each carbon–carbon bond: the torsion angle between the atoms or groups bound to the atoms at each end of the bond.
ðɛɹ ɪz ɐ fˈɜːðɚ dᵻɡɹˈiː ʌv fɹˈiːdəm fɔːɹ ˈiːtʃ kˈɑːɹbən kˈɑːɹbən bˈɑːnd: ðə tˈoːɹʃən ˈæŋɡəl bᵻtwˌiːn ðɪ ˈæɾəmz ɔːɹ ɡɹˈuːps bˈaʊnd tə ðɪ ˈæɾəmz æɾ ˈiːtʃ ˈɛnd ʌvðə bˈɑːnd.