A propellant comprising at least one hydrofluorocarbon selected from the group consisting of: CF 3 CF=CHCF 3, CF 3 CF 2 CF=CH 2, CF 3 CH=CHCF 3, CF 3 CF 2 CH=CH 2, CF 2 =CHCF 2 CF 3, CF 2 =CFCHFCF 3, CF 2 =CFCF 2 CHF 2, CHF 2 CH=CHCF 3, (CF 3) 2 C=CHCF 3, CF 3 CF=CHCF 2 CF 3, CF 3 CH=CFCF 2 CF 3, (CF 3) 2 CFCH=CH 2, CF 3 CF 2 CF 2 CH=CH 2, (CF 3) 2 CFCF=CHCF 3, CF 2 =CFCF 2 CH 2 F, CF 2 =CFCHFCHF 2, CH 2 =C(CF 3) 2, CH 2 CF 2 CF=CF 2, CH 2 FCF=CFCHF 2, CH 2 FCF 2 CF=CF 2, CF 2 =C(CF 3)(CH 3), CH 2 =C(CHF 2)(CF 3), CH 2 =CHCF 2 CHF 2, CF 2 =C(CHF 2)(CH 3), CHF=C(CF 3)(CH 3), CH 2 =C(CHF 2) 2, CF 3 CF=CFCH 3, CH 3 CF=CHCF 3, CHF=CFCF 2 CF 2 CF 3, CF 2 =CHCF 2 CF 2 CF 3, CF 2 =CFCF 2 CF 2 CHF 2, CHF 2 CF=CFCF 2 CF 3, CF 3 CF=CFCF 2 CHF 2, CF 3 CF=CFCHFCF 3, CHF=CFCF(CF 3) 2, CF 2 =CFCH(CF 3) 2, CF 3 CH=C(CF 3) 2, CF 2 =CHCF(CF 3) 2, CH 2 =CFCF 2 CF 2 CF 3, CHF=CFCF 2 CF 2 CHF 2, CH 2 =C(CF 3)CF 2 CF 3, CF 2 =CHCH(CF 3) 2, CHF=CHCF(CF 3) 2, CF 2 =C(CF 3)CH 2 CF 3, CH 2 =CFCF 2 CF 2 CHF 2, CF 2 =CHCF 2 CH 2 CF 3, CF 3 CF=C(CF 3)(CH 3), CH 2 =CFCH(CF 3) 2, CHF=CHCH(CF 3) 2, CH 2 FCH=C(CF 3) 2, CH 3 CF=C(CF 3) 2, CH 2 =CHCF 2 CHFCF 3, CH 2 C(CF 3)CH 2 CF 3, (CF 3) 2 C=CHC 2 F 5, (CF 3) 2 CFCF=CHCF 3, CH 2 =CHC(CF 3) 3, (CF 3) 2 C=C(CH 3)(CF 3), CH 2 =CFCF 2 CH(CF 3) 2, CF 3 CF=C(CH 3)CF 2 CF 3, CF 3 CH=CHCH(CF 3) 2, CH 2 =CHCF 2 CF 2 CF 2 CHF 2, (CF 3) 2 C=CHCF 2 CH 3, CH 2 =C(CF 3)CH 2 C 2 F 5, CH 2 =CHCH 2 CF 2 C 2 F 5, CH 2 =CHCH 2 CF 2 C 2 F 5, CF 3 CF 2 CF=CFC 2 H 5, CH 2 =CHCH 2 CF(CF 3) 2, CF 3 CF=CHCH(CF 3)(CH 3), (CF 3) 2 C=CFC 2 H5, cyclo-CF 2 CF 2 CF 2 CH=CH-, cyclo-CF 2 CF 2 CH=CH-, CF 3 CF 2 CF 2 C(CH 3)=CH 2, CF 3 CF 2 CF 2 CH=CHCH 3, CF 3 CF 2 CF 2 CF 2 CH=CH 2, CF 3 CH=CHCF 2 CF 3, CF 2 CF 2 CH=CHCF 2 CF 3, CF 3 CH=CHCF 2 CF 2 CF 3, CF 3 CH=CFCF 2 CF 2 C 2 F 5, CF 3 CF=CHCF 2 CF 2 C 2 F 5, CF 3 CF 2 CH=CFCF 2 C 2 F 5, CF 3 CF 2 CF=CHCF 2 C 2 F 5, C 2 F 5 CF 2 CF=CHCH 3, C 2 F 5 CF=CHCH 3, (CF 3) 2 C=CHCH 3, CF 3 C(CH 3)=CHCF 3, CHF=CFC 2 F 5, CHF 2 CF=CFCF 3, (CF 3) 2 C=CHF, CH 2 FCF=CFCF 3, CHF=CHCF 2 CF 3, CHF 2 CH=CFCF 3, CHF=CFCHFCF 3, CF 3 CH=CFCHF 2, CHF=CFCF 2 CHF 2, CHF 2 CF=CFCHF 2, CH 2 CF=CFCF 3, CH 2 FCH=CFCF 3, CH 2 =CFCHFCF 3, CH 2 =CFCF 2 CHF 2, CF 3 CH=CFCH 2 F, CHF=CFCH 2 CF 3, CHF=CHCHFCF 3, CHF=CHCF 2 CHF 2, CHF 2 CF=CHCHF 2, CHF=CFCHFCHF 2, and CF 3 CF=CHCH 3,. CF 3 CF=CHCF 3, CF 3 CF 2 CF=CH 2, CF 3 CH=CHCF 3, CF 3 CF 2 CH=CH 2, CF 2 =CHCF 2 CF 3, CF 2 =CFCHFCF 3, CF 2 =CFCF 2 CHF 2, CHF 2 CH=CHCF 3, (CF 3) 2 C=CHCF 3, CF 3 CF=CHCF 2 CF 3, CF 3 CH=CFCF 2 CF 3, (CF 3) 2 CFCH=CH 2, CF 3 CF 2 CF 2 CH=CH 2, (CF 3) 2 CFCF=CHCF 3, CF 2 =CFCF 2 CH 2 F, CF 2 =CFCHFCHF 2, CH 2 =C(CF 3) 2, CH 2 CF 2 CF=CF 2, CH 2 FCF=CFCHF 2, CH 2 FCF 2 CF=CF 2, CF 2 =C(CF 3)(CH 3), CH 2 =C(CHF 2)(CF 3), CH 2 =CHCF 2 CHF 2, CF 2 =C(CHF 2)(CH 3), CHF=C(CF 3)(CH 3), CH 2 =C(CHF 2) 2, CF 3 CF=CFCH 3, CH 3 CF=CHCF 3, CHF=CFCF 2 CF 2 CF 3, CF 2 =CHCF 2 CF 2 CF 3, CF 2 =CFCF 2 CF 2 CHF 2, CHF 2 CF=CFCF 2 CF 3, CF 3 CF=CFCF 2 CHF 2, CF 3 CF=CFCHFCF 3, CHF=CFCF(CF 3) 2, CF 2 =CFCH(CF 3) 2, CF 3 CH=C(CF 3) 2, CF 2 =CHCF(CF 3) 2, CH 2 =CFCF 2 CF 2 CF 3, CHF=CFCF 2 CF 2 CHF 2, CH 2 =C(CF 3)CF 2 CF 3, CF 2 =CHCH(CF 3) 2, CHF=CHCF(CF 3) 2, CF 2 =C(CF 3)CH 2 CF 3, CH 2 =CFCF 2 CF 2 CHF 2, CF 2 =CHCF 2 CH 2 CF 3, CF 3 CF=C(CF 3)(CH 3), CH 2 =CFCH(CF 3) 2, CHF=CHCH(CF 3) 2, CH 2 FCH=C(CF 3) 2, CH 3 CF=C(CF 3) 2, CH 2 =CHCF 2 CHFCF 3, CH 2 C(CF 3)CH 2 CF 3, (CF 3) 2 C=CHC 2 F 5, (CF 3) 2 CFCF=CHCF 3, CH 2 =CHC(CF 3) 3, (CF 3) 2 C=C(CH 3)(CF 3), CH 2 =CFCF 2 CH(CF 3) 2, CF 3 CF=C(CH 3)CF 2 CF 3, CF 3 CH=CHCH(CF 3) 2, CH 2 =CHCF 2 CF 2 CF 2 CHF 2, (CF 3) 2 C=CHCF 2 CH 3, CH 2 =C(CF 3)CH 2 C 2 F 5, CH 2 =CHCH 2 CF 2 C 2 F 5, CH 2 =CHCH 2 CF 2 C 2 F 5, CF 3 CF 2 CF=CFC 2 H 5, CH 2 =CHCH 2 CF(CF 3) 2, CF 3 CF=CHCH(CF 3)(CH 3), (CF 3) 2 C=CFC 2 H5, cyclo-CF 2 CF 2 CF 2 CH=CH-, cyclo-CF 2 CF 2 CH=CH-, CF 3 CF 2 CF 2 C(CH 3)=CH 2, CF 3 CF 2 CF 2 CH=CHCH 3, CF 3 CF 2 CF 2 CF 2 CH=CH 2, CF 3 CH=CHCF 2 CF 3, CF 2 CF 2 CH=CHCF 2 CF 3, CF 3 CH=CHCF 2 CF 2 CF 3, CF 3 CH=CFCF 2 CF 2 C 2 F 5, CF 3 CF=CHCF 2 CF 2 C 2 F 5, CF 3 CF 2 CH=CFCF 2 C 2 F 5, CF 3 CF 2 CF=CHCF 2 C 2 F 5, C 2 F 5 CF 2 CF=CHCH 3, C 2 F 5 CF=CHCH 3, (CF 3) 2 C=CHCH 3, CF 3 C(CH 3)=CHCF 3, CHF=CFC 2 F 5, CHF 2 CF=CFCF 3, (CF 3) 2 C=CHF, CH 2 FCF=CFCF 3, CHF=CHCF 2 CF 3, CHF 2 CH=CFCF 3, CHF=CFCHFCF 3, CF 3 CH=CFCHF 2, CHF=CFCF 2 CHF 2, CHF 2 CF=CFCHF 2, CH 2 CF=CFCF 3, CH 2 FCH=CFCF 3, CH 2 =CFCHFCF 3, CH 2 =CFCF 2 CHF 2, CF 3 CH=CFCH 2 F, CHF=CFCH 2 CF 3, CHF=CHCHFCF 3, CHF=CHCF 2 CHF 2, CHF 2 CF=CHCHF 2, CHF=CFCHFCHF 2, and CF 3 CF=CHCH 3,.