ðə kˌæɹɪktɚɹˈɪstɪk stˈeɪt fˈʌŋkʃən ɔːɹ mˈæsɪˌuːz pətˈɛnʃəl ɪn stɐtˈɪstɪkəl mᵻkˈænɪks ɹᵻfˈɜːz tʊ ɐ pɚtˈɪkjʊlɚ ɹᵻlˈeɪʃənʃˌɪp bᵻtwˌiːn ðə pɑːɹtˈɪʃən fˈʌŋkʃən əvən ɑːnsˈɑːmbəl.
The characteristic state function or Massieu's potential in statistical mechanics refers to a particular relationship between the partition function of an ensemble.