The CsFr molecule is polarised as Cs+Fr−, showing that the 7s subshell of francium is much more strongly affected by relativistic effects than the 6s subshell of caesium.
ðə sˌiːˈɛs ˌɛfˈɑːɹ mˈɑːlɪkjˌuːl ɪz pˈoʊlɚɹˌaɪzd æz sˌiːˈɛs plˈʌs ˌɛfˈɑːɹ mˈaɪnəs, ʃˈoʊɪŋ ðætðə sˈɛvən z sˈʌbʃɛl ʌv fɹˈænsiəm ɪz mˈʌtʃ mˈoːɹ stɹˈɔŋli ɐfˈɛktᵻd baɪ ɹˌɛləɾɪvˈɪstɪk ɪfˈɛkts ðɐn ðə sˈɪks ᵻz sˈʌbʃɛl ʌv sˈiːsiəm.