In highly branched alkanes, the bond angle may differ significantly from the optimal value (109.5°) to accommodate bulky groups.
ɪn hˈaɪli bɹˈæntʃt ˈælkeɪnz, ðə bˈɑːnd ˈæŋɡəl mˈeɪ dˈɪfɚ sɪɡnˈɪfɪkəntli fɹʌmðɪ ˈɑːptɪməl vˈæljuː wˈʌnhˈʌndɹɪd nˈaɪn.fˈaɪv dᵻɡɹˈiːz tʊ ɐkˈɑːmədˌeɪt bˈʌlki ɡɹˈuːps.