# Sn–U system

> Sn–U system: 57 accepted literature values (invariant reaction 38, formation 17, crystal structure 2) and 2 calculated phase diagram(s) from ORCHID, each value with evidence class, source, page and quote.

HTML: https://data.orchid-project.org/systems/SN-U.html · Markdown: https://data.orchid-project.org/systems/SN-U.md

57 accepted literature values from 2 paper(s) (experimental 32, model 19, unspecified 6); 2 calculated phase diagram(s). 11 further extracted value(s) not accepted by the reader-agreement checks are only in the JSON/CSV.

Data: [JSON](https://data.orchid-project.org/literature/systems/SN-U.json) · [CSV](https://data.orchid-project.org/systems/SN-U.csv) · [interactive explorer](https://orchid-project.org/data-explorer/#SN-U) · [interactive phase diagram](https://orchid-project.org/phase-diagrams/#SN-U/SnU-21Wan.json) · [phases (15)](https://data.orchid-project.org/phases/pages/SN-U.html) · [papers (bibliography)](https://data.orchid-project.org/bibliography/pages/systems/SN-U.html) · [Markdown](https://data.orchid-project.org/systems/SN-U.md)

Table: Accepted values by evidence class

| Evidence class | Values |
|---|---:|
| experimental | 32 |
| model | 19 |
| unspecified | 6 |

Table: Accepted values by property group

| Property group | Values |
|---|---:|
| invariant reaction | 38 |
| formation | 17 |
| crystal structure | 2 |

## Calculated phase diagrams

Binary phase diagrams calculated with pycalphad 0.11.2 from the SGTE binary collection (Hallstedt 2025, CC BY 4.0). Evidence class: model.

Table: Assessments with a calculated phase diagram

| TDB file | Assessment | SHA-256 | Links |
|---|---|---|---|
| SnU-21Wan.tdb | J. Wang, Y. Yuan, X. Cheng, Q. Zhang, R. Pan, A. Tang, J. Phase Equilib. Diffus., 42, 194-205(2021). [doi:10.1007/s11669-021-00872-2](https://doi.org/10.1007/s11669-021-00872-2) | `bfb5a924fae70c95f81592d4e6676e0f3df1ddeb1cc71e68f044d0e330ec6304` | [viewer](https://orchid-project.org/phase-diagrams/#SN-U/SnU-21Wan.json) · [TDB](https://orchid-project.org/data/databases/sgte-binary/SnU-21Wan.tdb) · [JSON](https://data.orchid-project.org/phase-diagrams/sgte/SnU-21Wan.json) |
| SnU-87She.tdb | R.I. Sheldon, E.M. Foltyn, D.E. Petersen, Bull. Alloy Phase Diag., 8, 347-52(1987). [doi:10.1007/BF02869271](https://doi.org/10.1007/BF02869271) | `52159592cd32f1c5864a9a901734f19ad59c34b4f1b04b2efb118b8b9f67c388` | [viewer](https://orchid-project.org/phase-diagrams/#SN-U/SnU-87She.json) · [TDB](https://orchid-project.org/data/databases/sgte-binary/SnU-87She.tdb) · [JSON](https://data.orchid-project.org/phase-diagrams/sgte/SnU-87She.json) |

Table: Calculated three-phase invariants (model, mole fraction of the second component)

| TDB file | T (K) | Phases at the invariant |
|---|---:|---|
| SnU-21Wan.tdb | 1661.44 | LIQUID (x(U) 0.48103) + SNU (x(U) 0.5) + SN4U5 (x(U) 0.55556) |
| SnU-21Wan.tdb | 1661.44 | LIQUID (x(U) 0.48045) + SNU (x(U) 0.5) + SN4U5 (x(U) 0.55556) |
| SnU-21Wan.tdb | 1661.44 | LIQUID (x(U) 0.48124) + SNU (x(U) 0.5) + SN4U5 (x(U) 0.55556) |
| SnU-21Wan.tdb | 1661.44 | LIQUID (x(U) 0.48126) + SNU (x(U) 0.5) + SN4U5 (x(U) 0.55556) |
| SnU-21Wan.tdb | 1627.22 | LIQUID (x(U) 0.27752) + SN2U (x(U) 0.33333) + SNU (x(U) 0.5) |
| SnU-21Wan.tdb | 1627.22 | LIQUID (x(U) 0.27731) + SN2U (x(U) 0.33333) + SNU (x(U) 0.5) |
| SnU-21Wan.tdb | 1627.22 | LIQUID (x(U) 0.27813) + SN2U (x(U) 0.33333) + SNU (x(U) 0.5) |
| SnU-21Wan.tdb | 1627.22 | LIQUID (x(U) 0.27815) + SN2U (x(U) 0.33333) + SNU (x(U) 0.5) |
| SnU-21Wan.tdb | 1627.22 | LIQUID (x(U) 0.27729) + SN2U (x(U) 0.33333) + SNU (x(U) 0.5) |
| SnU-21Wan.tdb | 1615.46 | LIQUID (x(U) 0.22612) + SN7U3 (x(U) 0.3) + SN2U (x(U) 0.33333) |
| SnU-21Wan.tdb | 1615.46 | LIQUID (x(U) 0.22665) + SN7U3 (x(U) 0.3) + SN2U (x(U) 0.33333) |
| SnU-21Wan.tdb | 1615.46 | LIQUID (x(U) 0.22551) + SN7U3 (x(U) 0.3) + SN2U (x(U) 0.33333) |
| SnU-21Wan.tdb | 1615.46 | LIQUID (x(U) 0.22663) + SN7U3 (x(U) 0.3) + SN2U (x(U) 0.33333) |
| SnU-21Wan.tdb | 1615.46 | LIQUID (x(U) 0.22551) + SN7U3 (x(U) 0.3) + SN2U (x(U) 0.33333) |
| SnU-21Wan.tdb | 1604 | LIQUID (x(U) 0.19212) + SN3U_L12 (x(U) 0.25) + SN7U3 (x(U) 0.3) |
| SnU-21Wan.tdb | 1604 | LIQUID (x(U) 0.19174) + SN3U_L12 (x(U) 0.25) + SN7U3 (x(U) 0.3) |
| SnU-21Wan.tdb | 1604 | LIQUID (x(U) 0.19123) + SN3U_L12 (x(U) 0.25) + SN7U3 (x(U) 0.3) |
| SnU-21Wan.tdb | 1604 | LIQUID (x(U) 0.19121) + SN3U_L12 (x(U) 0.25) + SN7U3 (x(U) 0.3) |
| SnU-21Wan.tdb | 1388.3 | SN4U5 (x(U) 0.55556) + LIQUID (x(U) 0.97172) + BCC_A2 (x(U) 0.98014) |
| SnU-21Wan.tdb | 1388.3 | SN4U5 (x(U) 0.55556) + LIQUID (x(U) 0.97193) + BCC_A2 (x(U) 0.98031) |
| SnU-21Wan.tdb | 1048.83 | SN4U5 (x(U) 0.55556) + BCC_A2 (x(U) 0.99991) + TETRAGONAL_U (x(U) 0.99999) |
| SnU-21Wan.tdb | 1048.83 | SN4U5 (x(U) 0.55556) + BCC_A2 (x(U) 0.99991) + TETRAGONAL_U (x(U) 0.99999) |
| SnU-21Wan.tdb | 942.02 | SN4U5 (x(U) 0.55556) + ORTHORHOMBIC_A20 (x(U) 1) + TETRAGONAL_U (x(U) 1) |
| SnU-21Wan.tdb | 505.08 | BCT_A5 (x(U) 0) + LIQUID (x(U) 0) + SN3U_L12 (x(U) 0.25) |
| SnU-87She.tdb | 1619.61 | SN5U3 (x(U) 0.375) + LIQUID (x(U) 0.37751) + SN2U3 (x(U) 0.6) |
| SnU-87She.tdb | 1619.61 | SN5U3 (x(U) 0.375) + LIQUID (x(U) 0.37785) + SN2U3 (x(U) 0.6) |
| SnU-87She.tdb | 1619.61 | SN5U3 (x(U) 0.375) + LIQUID (x(U) 0.37743) + SN2U3 (x(U) 0.6) |
| SnU-87She.tdb | 1603.15 | SN3U_L12 (x(U) 0.25) + LIQUID (x(U) 0.27789) + SN5U3 (x(U) 0.375) |
| SnU-87She.tdb | 1603.15 | SN3U_L12 (x(U) 0.25) + LIQUID (x(U) 0.27786) + SN5U3 (x(U) 0.375) |
| SnU-87She.tdb | 1353.59 | SN2U3 (x(U) 0.6) + LIQUID (x(U) 0.96209) + BCC_A2 (x(U) 0.99073) |
| SnU-87She.tdb | 1353.59 | SN2U3 (x(U) 0.6) + LIQUID (x(U) 0.9621) + BCC_A2 (x(U) 0.99073) |
| SnU-87She.tdb | 1047.33 | SN2U3 (x(U) 0.6) + BCC_A2 (x(U) 0.99914) + TETRAGONAL_U (x(U) 1) |
| SnU-87She.tdb | 1047.33 | SN2U3 (x(U) 0.6) + BCC_A2 (x(U) 0.99914) + TETRAGONAL_U (x(U) 1) |
| SnU-87She.tdb | 942.02 | SN2U3 (x(U) 0.6) + ORTHORHOMBIC_A20 (x(U) 1) + TETRAGONAL_U (x(U) 1) |
| SnU-87She.tdb | 505.08 | BCT_A5 (x(U) 0) + LIQUID (x(U) 0) + SN3U_L12 (x(U) 0.25) |

Convex hulls: [Materials Project DFT hull](https://data.orchid-project.org/hulls/dft-mp/SN/SN-U.json) · [OQMD DFT hull](https://data.orchid-project.org/hulls/dft-oqmd/SN/SN-U.json) · [CALPHAD hull SnU-87She](https://data.orchid-project.org/hulls/calphad-sgte/SN/SN-U--SnU-87She.json)

## Invariant reactions (literature)

Table: Invariant reactions reported in the literature for the Sn–U system (38)

| T (K) | Reaction / phases | Compositions (mole fraction) | Class | Source | Location | Quote |
|---:|---|---|---|---|---|---|
| 1773.15 | congruent melting: L -> Sn2U3 | L: Sn 0.4, U 0.6; Sn2U3: Sn 0.4, U 0.6 | model | [1] Sheldon 1987 | Table 1, p. 2, row 8; `ORC-D43FJK63HX` |  |
| 1773.15 | congruent melting: L -> Sn2U3 | L: U 0.6; Sn2U3: U 0.6 | model | [1] Sheldon 1987 | Table 1, p. 2, row 7; `ORC-F56UI7DFV2` |  |
| 1666.15 | congruent melting: Liquid->U5Sn4 | Liquid: U 0.556; U5Sn4: U 0.556 | experimental | [2] Wang 2021; _cites Wang 2016_ [doi](https://doi.org/10.1016/j.jct.2015.08.029) | Table 3, p. 7, row 3; `ORC-RAF46DPADC` |  |
| 1663.15 | congruent melting: Liquid->U5Sn4 | Liquid: U 0.556; U5Sn4: U 0.556 | model | [2] Wang 2021 | Table 3, p. 7, row 1; `ORC-4J2AM7X4OS` |  |
| 1663.15 | congruent melting: Liquid->U5Sn4 | Liquid: U 0.556; U5Sn4: U 0.556 | experimental | [2] Wang 2021; _cites Palenzona 1995_ [doi](https://doi.org/10.1016/0925-8388%2894%2901463-9) | Table 3, p. 7, row 2; `ORC-JWZJYNLQEB` |  |
| 1661.15 | peritectic: Liquid+U5Sn4->USn | Liquid: U 0.5; U5Sn4: U 0.556; USn: U 0.5 | model | [2] Wang 2021 | Table 3, p. 7, row 4; `ORC-B5E6CIUAST` |  |
| 1658.15 | peritectic: Liquid+U5Sn4->USn | Liquid: U 0.5; U5Sn4: U 0.556; USn: U 0.5 | experimental | [2] Wang 2021; _cites Palenzona 1995_ [doi](https://doi.org/10.1016/0925-8388%2894%2901463-9) | Table 3, p. 7, row 5; `ORC-4NH6QRNLZR` |  |
| 1655.15 | peritectic: Liquid+U5Sn4->USn | Liquid: U 0.5; U5Sn4: U 0.556; USn: U 0.5 | experimental | [2] Wang 2021; _cites Wang 2016_ [doi](https://doi.org/10.1016/j.jct.2015.08.029) | Table 3, p. 7, row 6; `ORC-A4NBK26GQC` |  |
| 1653.15 | peritectic: L + Sn2U3 -> Sn5U3 | L: U 0.333; Sn2U3: U 0.6; Sn5U3: U 0.375 | model | [1] Sheldon 1987 | Table 1, p. 2, row 5; `ORC-BYTM52AY2Z` |  |
| 1653.15 | peritectic: L + Sn2U3 -> Sn5U3 | L: U 0.338; Sn2U3: U 0.6; Sn5U3: U 0.375 | model | [1] Sheldon 1987 | Table 1, p. 2, row 6; `ORC-SIICULMYWG` |  |
| 1653.15 | peritectic |  | experimental | [1] Sheldon 1987; _cites ref. 45Tre_ | p. 3; `ORC-VYDAMHKF53` | “B a s e d on m e t a l l o g r a p h i c a n d t h e r m a l a n a l y s i s data, the composition of t h i s compound was proposed by \[45Tre\] to be Sn~U3, with a peritectic decomposition a t 1380 ~” |
| 1633.15 | peritectic: Liquid+USn->USn2 | USn: U 0.5; USn2: U 0.3333 | experimental | [2] Wang 2021; _cites Palenzona 1995_ [doi](https://doi.org/10.1016/0925-8388%2894%2901463-9) | Table 3, p. 7, row 8; `ORC-AW2LXFNT4A` |  |
| 1633.15 | peritectic: Liquid+USn->USn2 | Liquid: U 0.2903; USn: U 0.5; USn2: U 0.3333 | model | [2] Wang 2021 | Table 3, p. 7, row 7; `ORC-LIQJIQXGJX` |  |
| 1633.15 | peritectic: Liquid+USn->USn2 | Liquid: U 0.256; USn: U 0.5; USn2: U 0.3333 | experimental | [2] Wang 2021; _cites Wang 2016_ [doi](https://doi.org/10.1016/j.jct.2015.08.029) | Table 3, p. 7, row 9; `ORC-OPIHYVRR2X` |  |
| 1623.15 | peritectic: Liquid+USn2->U3Sn7 | USn2: U 0.3333; U3Sn7: U 0.3 | experimental | [2] Wang 2021; _cites Palenzona 1995_ [doi](https://doi.org/10.1016/0925-8388%2894%2901463-9) | Table 3, p. 7, row 11; `ORC-AVVM37L4K7` |  |
| 1623.15 | peritectic: Liquid+USn2->U3Sn7 | Liquid: U 0.235; USn2: U 0.3333; U3Sn7: U 0.3 | model | [2] Wang 2021 | Table 3, p. 7, row 10; `ORC-JPJP3TT3V2` |  |
| 1623.15 | peritectic: L + Sn5U3 -> Sn3U | L: U 0.232; Sn5U3: U 0.375; Sn3U: U 0.25 | model | [1] Sheldon 1987 | Table 1, p. 2, row 3; `ORC-OXMAC3HAFG` |  |
| 1623.15 | peritectic: L + Sn5U3 -> Sn3U | L: U 0.244; Sn5U3: U 0.375; Sn3U: U 0.25 | model | [1] Sheldon 1987 | Table 1, p. 2, row 4; `ORC-WH5E3QH3RC` |  |
| 1623.15 | peritectic |  | experimental | [1] Sheldon 1987; _cites ref. 45Tre_ | p. 3; `ORC-Y3MS7TEPHM` | “\[45Tre\| reported this compound decomposes peritectically at 1350 ~” |
| 1623.15 | peritectic: Liquid+USn2->U3Sn7 | Liquid: U 0.221; USn2: U 0.3333; U3Sn7: U 0.3 | experimental | [2] Wang 2021; _cites Wang 2016_ [doi](https://doi.org/10.1016/j.jct.2015.08.029) | Table 3, p. 7, row 12; `ORC-ZUI32ZHHM5` |  |
| 1613.15 | peritectic: Liquid+U3Sn7->USn3 | U3Sn7: U 0.3; USn3: U 0.25 | experimental | [2] Wang 2021; _cites Palenzona 1995_ [doi](https://doi.org/10.1016/0925-8388%2894%2901463-9) | Table 3, p. 7, row 14; `ORC-DUNOKQ5G3E` |  |
| 1613.15 | peritectic: Liquid+U3Sn7->USn3 | Liquid: U 0.196; U3Sn7: U 0.3; USn3: U 0.25 | experimental | [2] Wang 2021; _cites Wang 2016_ [doi](https://doi.org/10.1016/j.jct.2015.08.029) | Table 3, p. 7, row 15; `ORC-I5NKTMW54E` |  |
| 1613.15 | peritectic: Liquid+U3Sn7->USn3 | Liquid: U 0.1982; U3Sn7: U 0.3; USn3: U 0.25 | model | [2] Wang 2021 | Table 3, p. 7, row 13; `ORC-MR5QVZ247Y` |  |
| 1408.15 | eutectic: L -> Sn2U3 + γU | L: U 0.999; Sn2U3: U 0.6; γU: U 1 | model | [1] Sheldon 1987 | Table 1, p. 2, row 9; `ORC-NZBCSWYGZB` |  |
| 1402.15 | eutectic: Liquid->bcc_A2+U5Sn4 | Liquid: U 0.97; bcc_A2: U 0.984; U5Sn4: U 0.556 | experimental | [2] Wang 2021; _cites Wang 2016_ [doi](https://doi.org/10.1016/j.jct.2015.08.029) | Table 3, p. 7, row 18; `ORC-VUYBZPGEVG` |  |
| 1393.15 | eutectic: Liquid->bcc_A2+U5Sn4 | Liquid: U 0.88; U5Sn4: U 0.556 | experimental | [2] Wang 2021; _cites Palenzona 1995_ [doi](https://doi.org/10.1016/0925-8388%2894%2901463-9) | Table 3, p. 7, row 17; `ORC-GY6PCQHPOG` |  |
| 1388.15 | eutectic: Liquid->bcc_A2+U5Sn4 | Liquid: U 0.9682; bcc_A2: U 0.9661; U5Sn4: U 0.556 | model | [2] Wang 2021 | Table 3, p. 7, row 16; `ORC-K6CVKSRNEJ` |  |
| 1354.15 | eutectic: L -> Sn2U3 + γU | L: U 0.97; Sn2U3: U 0.6; γU: U 1 | model | [1] Sheldon 1987 | Table 1, p. 2, row 10; `ORC-YEMYD7U36Y` |  |
| 1049.15 | eutectoid: bcc_U->U5Sn4+Tetragonal_U | bcc_U: U 0.9953; U5Sn4: U 0.556; Tetragonal_U: U 0.9954 | experimental | [2] Wang 2021; _cites Wang 2016_ [doi](https://doi.org/10.1016/j.jct.2015.08.029) | Table 3, p. 7, row 21; `ORC-45T752MFSP` |  |
| 1049.15 | eutectoid: bcc_U->U5Sn4+Tetragonal_U | U5Sn4: U 0.556 | experimental | [2] Wang 2021; _cites Palenzona 1995_ [doi](https://doi.org/10.1016/0925-8388%2894%2901463-9) | Table 3, p. 7, row 20; `ORC-6K47UL4U3W` |  |
| 1049.15 | eutectoid: bcc_U->U5Sn4+Tetragonal_U | bcc_U: U 0.9999; U5Sn4: U 0.556; Tetragonal_U: U 1 | model | [2] Wang 2021 | Table 3, p. 7, row 19; `ORC-QVLOF4IWH5` |  |
| 942.15 | eutectoid: Tetragonal_U+U5Sn4->Orthorhombic_U | Tetragonal_U: U 1; U5Sn4: U 0.556; Orthorhombic_U: U 1 | model | [2] Wang 2021 | Table 3, p. 7, row 22; `ORC-C23M7WUCUC` |  |
| 941.15 | eutectoid: Tetragonal_U+U5Sn4->Orthorhombic_U | Tetragonal_U: U 0.9971; U5Sn4: U 0.556; Orthorhombic_U: U 0.9968 | experimental | [2] Wang 2021; _cites Wang 2016_ [doi](https://doi.org/10.1016/j.jct.2015.08.029) | Table 3, p. 7, row 24; `ORC-6MJFWGLDP7` |  |
| 938.15 | eutectoid: Tetragonal_U+U5Sn4->Orthorhombic_U | U5Sn4: U 0.556 | experimental | [2] Wang 2021; _cites Palenzona 1995_ [doi](https://doi.org/10.1016/0925-8388%2894%2901463-9) | Table 3, p. 7, row 23; `ORC-ADK5RKNRF7` |  |
| 505.15 | eutectic: Liquid->USn3+bct_Sn | Liquid: U 0; USn3: U 0.25; bct_Sn: U 0 | model | [2] Wang 2021 | Table 3, p. 7, row 25; `ORC-ANYYPGZSVH` |  |
| 505.15 | eutectic: Liquid->USn3+bct_Sn | USn3: U 0.25 | experimental | [2] Wang 2021; _cites Palenzona 1995_ [doi](https://doi.org/10.1016/0925-8388%2894%2901463-9) | Table 3, p. 7, row 26; `ORC-BDRUVR2TKO` |  |
| 505.15 | eutectic: Liquid->USn3+bct_Sn | Liquid: U 0; USn3: U 0.25; bct_Sn: U 0 | experimental | [2] Wang 2021; _cites Wang 2016_ [doi](https://doi.org/10.1016/j.jct.2015.08.029) | Table 3, p. 7, row 27; `ORC-BUG7BO7SUM` |  |
| 505.15 | other: L -> βSn | L: U 0; βSn: U 0 | model | [1] Sheldon 1987 | Table 1, p. 2, row 1; `ORC-GMURNCPCTT` |  |

## Formation enthalpies

Literature values in kJ/mol-atom where the per-atom basis is known. DFT columns: the lowest-energy entry at the same composition (Materials Project 2026.04.13, OQMD v1.8; different energy references, never averaged), from [dft_parity.json](https://data.orchid-project.org/literature/dft_parity.json).

Table: Enthalpies of formation, Sn–U system (17)

| Phase | Compound | Value | T (K) | Class | MP DFT (kJ/mol-atom) | OQMD DFT (kJ/mol-atom) | Source | Location | Quote |
|---|---|---:|---:|---|---:|---:|---|---|---|
| U3Sn7 | [Sn7U3](https://data.orchid-project.org/compounds/Sn7U3.html) | -52.78 kJ/mol-atom | 794.15 | unspecified | -12.21 (mp-aaacqpmz) |  | [2] Wang 2021; _cites Palenzona 1995_ [doi](https://doi.org/10.1016/0925-8388%2894%2901463-9) | Table 1, p. 3, row 4; `ORC-UGUP3IIIUE` |  |
| USn | [SnU](https://data.orchid-project.org/compounds/SnU.html) | -88.45 kJ/mol-atom | 794.15 | unspecified | 4.115 (mp-aaacdipr) | -2.203 (oqmd-1231159) | [2] Wang 2021; _cites Palenzona 1995_ [doi](https://doi.org/10.1016/0925-8388%2894%2901463-9) | Table 1, p. 3, row 2; `ORC-HBOMRR3WMD` |  |
| USn2 | [Sn2U](https://data.orchid-project.org/compounds/Sn2U.html) | -58.3 kJ/mol-atom | 794.15 | unspecified | -9.73 (mp-aaacqroo) |  | [2] Wang 2021; _cites Palenzona 1995_ [doi](https://doi.org/10.1016/0925-8388%2894%2901463-9) | Table 1, p. 3, row 3; `ORC-BK7CRI65KP` |  |
| USn3 | [Sn3U](https://data.orchid-project.org/compounds/Sn3U.html) | -43.47 kJ/mol-atom | 794.15 | experimental | -12.058 (mp-aaaabece) | -19.098 (oqmd-18132) | [2] Wang 2021; _cites Colinet 1988_ [doi](https://doi.org/10.1016/0022-5088%2888%2990049-5) | Table 1, p. 3, row 10; `ORC-RYIOBWSPT5` |  |
| USn3 |  | -43.47 kJ/mol (basis unstated) | 794.15 | experimental |  |  | [2] Wang 2021; _cites Colinet 1988_ [doi](https://doi.org/10.1016/0022-5088%2888%2990049-5) | p. 2; `ORC-V3325OI2BY.534bcb` | “Colinet et al.\[26\] reported the enthalpy of formation of USn3 as - 35.3 kJ mol-1 at 25 C and - 43.47 kJ mol-1 at 521 C characterized by solution calorimetry analysis.” |
| USn3 | [Sn3U](https://data.orchid-project.org/compounds/Sn3U.html) | -43.2 kJ/mol-atom | 794.15 | experimental | -12.058 (mp-aaaabece) | -19.098 (oqmd-18132) | [2] Wang 2021; _cites Pattanaik 2013_ [doi](https://doi.org/10.1016/j.jallcom.2012.09.144) | Table 1, p. 3, row 11; `ORC-PQRCDHMBVC` |  |
| USn3 | [Sn3U](https://data.orchid-project.org/compounds/Sn3U.html) | -42.9 kJ/mol-atom | 965.15 | experimental | -12.058 (mp-aaaabece) | -19.098 (oqmd-18132) | [2] Wang 2021; _cites Kadochnikov 1976_ | Table 1, p. 3, row 12; `ORC-3LMSC4VP4N` |  |
| USn3 |  | -41.8 kJ/mol (basis unstated) | 794.15 | experimental |  |  | [2] Wang 2021; _cites Johnson 1962_ | p. 2; `ORC-6LXQ4ZX6BF.380e28` | “Johnson et al.\[24\] reported the enthalpy of formation of USn3 as - 36.5 kJ mol-1 at 25 C and - 41.8 kJ mol-1 at 521 C using emf measurements.” |
| USn3 | [Sn3U](https://data.orchid-project.org/compounds/Sn3U.html) | -41.8 kJ/mol-atom | 794.15 | unspecified | -12.058 (mp-aaaabece) | -19.098 (oqmd-18132) | [2] Wang 2021; _cites Sheldon 1987_ [doi](https://doi.org/10.1007/bf02869271) | Table 1, p. 3, row 9; `ORC-Q3DN6PXNB2` |  |
| USn3 |  | -36.5 kJ/mol (basis unstated) | 298.15 | experimental |  |  | [2] Wang 2021; _cites Johnson 1962_ | p. 2; `ORC-6LXQ4ZX6BF.da4161` | “Johnson et al.\[24\] reported the enthalpy of formation of USn3 as - 36.5 kJ mol-1 at 25 C and - 41.8 kJ mol-1 at 521 C using emf measurements.” |
| USn3 | [Sn3U](https://data.orchid-project.org/compounds/Sn3U.html) | -36.5 kJ/mol-atom | 298.15 | experimental | -12.058 (mp-aaaabece) | -19.098 (oqmd-18132) | [2] Wang 2021; _cites Johnson 1962_ | Table 1, p. 3, row 6; `ORC-D54TJXDZAE` |  |
| USn3 |  | -35.3 kJ/mol (basis unstated) | 298.15 | experimental |  |  | [2] Wang 2021; _cites Colinet 1988_ [doi](https://doi.org/10.1016/0022-5088%2888%2990049-5) | p. 2; `ORC-V3325OI2BY.534b78` | “Colinet et al.\[26\] reported the enthalpy of formation of USn3 as - 35.3 kJ mol-1 at 25 C and - 43.47 kJ mol-1 at 521 C characterized by solution calorimetry analysis.” |
| USn3 | [Sn3U](https://data.orchid-project.org/compounds/Sn3U.html) | -35.3 kJ/mol-atom | 298.15 | experimental | -12.058 (mp-aaaabece) | -19.098 (oqmd-18132) | [2] Wang 2021; _cites Colinet 1988_ [doi](https://doi.org/10.1016/0022-5088%2888%2990049-5) | Table 1, p. 3, row 7; `ORC-VRQVJOHN5X` |  |
| USn3 |  | -24.06 kJ/mol (basis unstated) | 794.15 | experimental |  |  | [2] Wang 2021; _cites Alcock 1962_ | p. 2; `ORC-FF7XAD26OS.5d3acf` | “For the thermodynamic properties of U-Sn binary system, Alcock et al.\[22\] reported the enthalpy of formation of USn3 as - 22.59 kJ mol-1 at 25 C using acid dissociation calorimetry and - 24.06 kJ mol-1 at 521 C using vapor pressure.” |
| USn3 | [Sn3U](https://data.orchid-project.org/compounds/Sn3U.html) | -24.06 kJ/mol-atom | 794.15 | experimental | -12.058 (mp-aaaabece) | -19.098 (oqmd-18132) | [2] Wang 2021; _cites Alcock 1962_ | Table 1, p. 3, row 8; `ORC-IHMGOGARKA` |  |
| USn3 |  | -22.59 kJ/mol (basis unstated) | 298.15 | experimental |  |  | [2] Wang 2021; _cites Alcock 1962_ | p. 2; `ORC-FF7XAD26OS.d77d6a` | “For the thermodynamic properties of U-Sn binary system, Alcock et al.\[22\] reported the enthalpy of formation of USn3 as - 22.59 kJ mol-1 at 25 C using acid dissociation calorimetry and - 24.06 kJ mol-1 at 521 C using vapor pressure.” |
| USn3 | [Sn3U](https://data.orchid-project.org/compounds/Sn3U.html) | -22.59 kJ/mol-atom | 298.15 | unspecified | -12.058 (mp-aaaabece) | -19.098 (oqmd-18132) | [2] Wang 2021; _cites Palenzona 1995_ [doi](https://doi.org/10.1016/0925-8388%2894%2901463-9) | Table 1, p. 3, row 5; `ORC-NFN2F33S26` |  |

## Other properties

### Crystal structure (2)

Table: Crystal structure, Sn–U system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Lattice a | 4.6089 Å | 298.15 | Sn3U; _alloy: Sn 0.75, U 0.25_ | model | [1] Sheldon 1987; _cites Sari 1983_ | Table 3, p. 3, row 9; `ORC-ANI26BZ4ZM` |  |
| Lattice a | 4.626 Å | 298.15 | Sn3U; _Sn3U: Sn 0.75, U 0.25_ | unspecified | [1] Sheldon 1987 | Table 3, p. 3, row 3; `ORC-HE4O3CF44X` |  |

## Sources

Reporting papers the values were read from (a value cited from another work names that work in its row).

1. R. I. Sheldon, E. M. Foltyn, D. E. Peterson, The Sn-U (Tin-Uranium) system, Bulletin of Alloy Phase Diagrams 8, 347-352 (1987). [doi:10.1007/bf02869271](https://doi.org/10.1007/bf02869271)
2. Jun Wang, Yuan Yuan, Xiongying Cheng, Qin Zhang, Rongjian Pan, Aitao Tang, Thermodynamic Assessment of the U-Sn System and Extension to the U-Zr-Sn System, J. Phase Equilib. Diffus. 42, 194-205 (2021). [doi:10.1007/s11669-021-00872-2](https://doi.org/10.1007/s11669-021-00872-2)

## Please cite

- R. Arróyave, J. Saal, D. Shin, ORCHID-Values: thermodynamic and phase-equilibrium values read from the literature (version 2026.10; Version 1, machine-extracted), Zenodo (2026). https://doi.org/10.5281/zenodo.23735569
- R. Arróyave, J. Saal, D. Shin, ORCHID-Diagrams: calculated binary phase diagrams (version 2026.10), Zenodo (2026). https://doi.org/10.5281/zenodo.23735859
- R. Arróyave, J. Saal, D. Shin, ORCHID-Hulls: binary convex hulls (Materials Project, OQMD, assessed CALPHAD) (version 2026.10), Zenodo (2026). https://doi.org/10.5281/zenodo.23735891
- R. Arróyave, J. Saal, D. Shin, ORCHID data: umbrella record of the ORCHID datasets (version 2026.10; Version 1, machine-extracted), Zenodo (2026). https://doi.org/10.5281/zenodo.23736065

Also cite the original source of every value you use (paper_citation / paper_doi, and cited_dois for values the paper cites from earlier work); B. Hallstedt, The SGTE collection of binary datasets, Calphad 89 (2025) 102833, https://doi.org/10.1016/j.calphad.2025.102833 (CC BY 4.0), and the original assessment named in each file; A. Jain et al., The Materials Project: A materials genome approach to accelerating materials innovation, APL Materials 1 (2013) 011002, https://doi.org/10.1063/1.4812323 (CC BY 4.0); J. E. Saal et al., JOM 65 (2013) 1501, https://doi.org/10.1007/s11837-013-0755-4 and S. Kirklin et al., npj Comput. Mater. 1 (2015) 15010, https://doi.org/10.1038/npjcompumats.2015.10 (CC BY 4.0).

Version 1, machine-extracted: values were read by language-model readers constrained to quote their source and checked automatically, and the release was then audited on the printed pages by adversarial audits, an independent second review of fit-facing records and a preliminary human review of a frozen sample. Flags such as accepted and ESPEI-ready record screening results, not certification; known issues are listed in the release notes.

```bibtex
@misc{orchid_literature_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Values: thermodynamic and phase-equilibrium values read from the literature}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735569},
  url       = {https://doi.org/10.5281/zenodo.23735569},
  note      = {Version 1, machine-extracted}
}

@misc{orchid_phase_diagrams_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Diagrams: calculated binary phase diagrams}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735859},
  url       = {https://doi.org/10.5281/zenodo.23735859}
}

@misc{orchid_hulls_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Hulls: binary convex hulls (Materials Project, OQMD, assessed CALPHAD)}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735891},
  url       = {https://doi.org/10.5281/zenodo.23735891}
}

@misc{orchid_data_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID data: umbrella record of the ORCHID datasets}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23736065},
  url       = {https://doi.org/10.5281/zenodo.23736065},
  note      = {Version 1, machine-extracted}
}
```

---

Derived data CC BY 4.0 ([licence](https://creativecommons.org/licenses/by/4.0/)): cite ORCHID ([CITATION.cff](https://data.orchid-project.org/CITATION.cff)) and the original sources. Quotes are short excerpts kept so that each value can be checked; they remain under the publishers' copyright and are not relicensed. Source papers, page images and full text are not redistributed. Field reference: [SCHEMA.md](https://data.orchid-project.org/literature/SCHEMA.md). Machine-readable guide: [llms.txt](https://data.orchid-project.org/llms.txt). Found an error? The report link of a value (Markdown: its id, ORC-..., in the Location column) opens a pre-filled GitHub issue, https://github.com/orchid-calphad/orchid-data/issues/new?template=report-value-error.yml&record_id=\<id>, carrying only the record id, source and value; [how to contribute](https://orchid-project.org/contribute/).