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We provide here recommended secondary reference points phase-transition temperatures for use as companion fixed points on ITS-90, along with uncertainties. We also provide references (generally multiple) to the literature for all secondary reference points. These data and references are provided in the section References for Temperature Points.
Instruction:Substance | Transition | T90 (K)
| u(T90) (K)
| Squib | More Data |
|---|---|---|---|---|---|
| Zn | SC | 0.8500 | 0.0030 | manage_search | |
| Al | SC | 1.181 | 0.003 | manage_search | |
| 4He | SF | 2.1768 | 0.0008 | manage_search | |
| In | SC | 3.4145 | 0.0025 | manage_search | |
| He | BP | 4.2238 | 0.0001 | manage_search | |
| Pb | SC | 7.1997 | 0.0025 | manage_search | |
| Nb | SC | 9.288 | 0.003 | manage_search | |
| p-H2 | TP | 13.8033 | na | manage_search | |
| n-H2 | TP | 13.952 | 0.002 | manage_search | |
| o-H2 | TP | 14.008 | na | manage_search | |
| e-D2 | TP | 18.6889 | 0.0003 | manage_search | |
| n-D2 | TP | 18.724 | na | manage_search | |
| p-H2 | BP | 20.271 | na | manage_search | |
| n-H2 | BP | 20.3689 | 0.0034 | manage_search | |
| o-H2 | β-γ | 20.38 | na | manage_search | |
| Methane | α-β | 20.45 | 0.01 | manage_search | |
| e-D2 | BP | 23.66 | 0.03 | manage_search | |
| O2 | (α-β)' | 23.814 | 0.008 | manage_search | |
| O2 | α-β | 23.89485 | 0.00006 | manage_search | |
| Ne-20 | TP | 24.5406 | 0.0006 | manage_search | |
| Ne | BP | 27.100 | 0.003 | manage_search | |
| N2 | α-β | 35.614 | 0.006 | manage_search | |
| O2 | β-γ | 43.7991 | 0.0015 | manage_search | |
| N2 | TP | 63.1507 | 0.0001 | manage_search | |
| N2 | BP | 77.3550 | 0.0008 | manage_search | |
| Ar | MP | 83.814 | na | manage_search | |
| Propane | TP | 85.52 | 0.01 | manage_search | |
| Ar | BP | 87.303 | 0.002 | manage_search | |
| O2 | BP | 90.1878 | 0.005 | manage_search | |
| O2 | CP | 90.197 | 0.001 | manage_search | |
| Ethane | TP | 90.36 | 0.06 | manage_search | |
| Methane | TP | 90.6941 | 0.0025 | manage_search | |
| Chlorotrifluoromethane | TP | 92 | na | manage_search | |
| Ethylene | TP | 103.986 | na | manage_search | |
| Methane | BP | 111.668 | 0.0025 | manage_search | |
| Kr | TP | 115.775 | 0.001 | manage_search | |
| Kr | BP | 119.735 | 0.013 | manage_search | |
| Fluoroethane | TP | 130 | na | manage_search | |
| 1,1-Difluoroethane | TP | 154.56 | na | manage_search | |
| 1,1,1-Trifluoroethane | TP | 161.34 | na | manage_search | |
| Xe | TP | 161.4059 | 0.0003 | manage_search | |
| Trichlorofluoromethane | TP | 162.678 | 0.002 | manage_search | |
| Xe | BP | 165.068 | 0.001 | manage_search | |
| Ethylene | BP | 169.379 | 0.004 | manage_search | |
| 1,1,1,2-Tetrafluoroethane | TP | 169.85 | na | manage_search | |
| Pentafluoroethane | TP | 172.52 | na | manage_search | |
| Hexafluoroethane | TP | 173.1 | na | manage_search | |
| Ethane | BP | 184.5686 | 0.0009 | manage_search | |
| Acetylene | BP | 188.26 | na | manage_search | |
| Chlorotrifluoromethane | BP | 191.674 | 0.009 | manage_search | |
| Acetylene | TP | 191.75 | na | manage_search | |
| CO2 | SP | 194.685 | 0.003 | manage_search | |
| Hexafluoroethane | BP | 195.06 | 0.03 | manage_search | |
| CO2 | TP | 216.5909 | 0.0004 | manage_search | |
| SF6 | TP | 223.5561 | 0.0004 | manage_search | |
| Pentafluoroethane | BP | 225.06 | 0.01 | manage_search | |
| 1,1,1-Trifluoroethane | BP | 225.909 | 0.011 | manage_search | |
| Propane | BP | 231.036 | 0.002 | manage_search | |
| Hg | FP | 234.3210 | 0.0005 | manage_search | |
| Fluoroethane | BP | 235.61 | 0.02 | manage_search | |
| Bromobenzene | TP | 242.426 | 0.010 | manage_search | |
| 1,1,1,2-Tetrafluoroethane | BP | 247.076 | 0.002 | manage_search | |
| 1,1-Difluoroethane | BP | 249.127 | 0.011 | manage_search | |
| H2O | IP | 273.15 | <0.0001 | manage_search | |
| Benzene | TP | 278.674 | na | manage_search | |
| GaIn - 20.5% | eut | 288.800 | 0.001 | manage_search | |
| GaSn - 8% | eut | 293.626 | 0.002 | manage_search | |
| Diphenylether | TP | 300.014 | 0.001 | manage_search | |
| Ga | TP | 302.9166 | 0.0001 | manage_search | |
| Ethylene Carbonate | TP | 309.465 | 0.001 | manage_search | |
| Icosane | TP | 309.63 | 0.01 | manage_search | |
| Rb | TP | 312.453 | 0.002 | manage_search | |
| Succinonitrile | TP | 331.215 | 0.002 | manage_search | |
| Benzene | BP | 353.219 | 0.03 | manage_search | |
| Na | FP | 370.944 | 0.005 | manage_search | |
| H2O | BP | 373.124 | 0.001 | manage_search | |
| H2O | BP | 373.1243 | 0.0035 | manage_search | |
| Benzoic Acid | TP | 395.486 | 0.002 | manage_search | |
| Benzoic Acid | FP | 395.508 | 0.005 | manage_search | |
| In | TP | 429.8038 | 0.0004 | manage_search | |
| Li-C | eut | 438 | 3 | manage_search | |
| Bi | FP | 544.553 | 0.001 | manage_search | |
| Cd | FP | 594.2186 | 0.0002 | manage_search | |
| Pb | FP | 600.612 | 0.001 | manage_search | |
| Hg | BP | 629.811 | 0.004 | manage_search | |
| S | BP | 717.674 | 0.002 | manage_search | |
| CuAl - 66.9% | eut | 821.308 | 0.010 | manage_search | |
| AgAl - 30% | eut | 840.957 | 0.002 | manage_search | |
| Sb | FP | 903.778 | 0.001 | manage_search | |
| CuAg - 71.9% | eut | 1052.78 | 0.05 | manage_search | |
| NaCl | FP | 1075.168 | 0.011 | manage_search | |
| Na | BP | 1156.09 | 0.05 | manage_search | |
| Cu-C | peri | 1373 | 1 | manage_search | |
| Fe3C-C | eut(th) | 1427.02 | 0.08 | manage_search | |
| Co-C | eut(th) | 1597.48 | 0.06 | manage_search | |
| Ni-C | eut | 1602.17 | 0.14 | manage_search | |
| Mn7C3-C | peri | 1603.87 | 0.2 | manage_search | |
| Si-SiC | eut | 1679.9 | 0.1 | manage_search | |
| Li2O | MP | 1711 | 5 | manage_search | |
| Ni | FP | 1728 | 1 | manage_search |
