# Ga–U phases

> Ga–U system: 11 phases (tier A 7, tier C 1, liquid 1, needs_review 2); 9 stable in a calculated diagram in the ORCHID phase registry, with names, structure type when the stored evidence supports an assignment under the stated tier rules, calculated stability, verbatim TDB PHASE/CONSTITUENT statements and example references.

HTML: https://data.orchid-project.org/phases/pages/GA-U.html · Markdown: https://data.orchid-project.org/phases/pages/GA-U.md

11 phases (tier A 7, tier C 1, liquid 1, needs_review 2); 9 stable in a calculated diagram. Structure types are assigned only when the stored evidence supports an assignment under the stated tier rules (tier A: standard phase name; tier B: unique Materials Project + OQMD on-hull match, DFT-supported; tier C: one structure stated by the assessment's crystallographic table, assessor-stated); other phases list candidates and are marked needs_review. Stability is from phase diagrams calculated with pycalphad from the SGTE binary collection (evidence class: model).

Data: [interactive registry](https://orchid-project.org/phases/?q=GA-U) · [full JSON](https://data.orchid-project.org/phases/systems/GA-U.json) · [Ga–U system page](https://data.orchid-project.org/systems/GA-U.html) · [Markdown](https://data.orchid-project.org/phases/pages/GA-U.md) · [field reference](https://data.orchid-project.org/phases/SCHEMA.md)

Table: Phases of the Ga–U system (11)

| Phase | Structure | Basis | Stability (calculated) | Literature values | TDB models |
|---|---|---|---|---:|---:|
| [ORTHORHOMBIC_A11](#phase-ga-u-a11-orthorhombic); _phase:ga-u:a11-orthorhombic_ | alpha-Ga · A11 · oC8 · Cmce (64) | tier A: standard phase name | stable in 2 of 2 calculated diagram(s): 300–940 K, x(U) 0–1 | 0 | 2 |
| [ORTHORHOMBIC_A20](#phase-ga-u-a20-orthorhombic); _phase:ga-u:a20-orthorhombic_ | alpha-U · A20 · oC4 · Cmcm (63) | tier A: standard phase name | stable in 2 of 2 calculated diagram(s): 300–1048.28 K, x(U) 0–1 | 6 | 2 |
| [BCC_A2](#phase-ga-u-bcc-a2); _phase:ga-u:bcc-a2_ | W · A2 · cI2 · Im-3m (229) | tier A: standard phase name | stable in 2 of 2 calculated diagram(s): 1006.58–1408.98 K, x(U) 0.9078–1 | 7 | 2 |
| [FCC_A1](#phase-ga-u-fcc-a1); _phase:ga-u:fcc-a1_ | Cu · A1 · cF4 · Fm-3m (225) | tier A: standard phase name | not stable in 2 calculated diagram(s) | 0 | 2 |
| [GA2U_C32](#phase-ga-u-ga2u-c32); _phase:ga-u:ga2u-c32_ | AlB2 · C32 · hP3 · P6/mmm (191) | tier A: standard phase name | stable in 2 of 2 calculated diagram(s): 300–1659.6 K, x(U) 0.33333–0.33333 | 10 | 2 |
| [GA3U_L12](#phase-ga-u-ga3u-l12); _phase:ga-u:ga3u-l12_ | AuCu3 · L1_2 · cP4 · Pm-3m (221) | tier A: standard phase name | stable in 2 of 2 calculated diagram(s): 300–1556.93 K, x(U) 0.25–0.25 | 3 | 2 |
| [GA3U2](#phase-ga-u-ga3u2); _phase:ga-u:ga3u2_ | Pd5Pu3 · oC32 · Cmcm (63) | tier C: assessor-stated (Hallstedt 2025 crystallographic table) | stable in 1 of 1 calculated diagram(s): 300–1532.19 K, x(U) 0.4–0.4 | 8 | 1 |
| [GA5U3](#phase-ga-u-ga5u3); _phase:ga-u:ga5u3_ |  | needs_review | stable in 1 of 1 calculated diagram(s): 300–1535.71 K, x(U) 0.375–0.375 | 4 | 1 |
| [HCP_A3](#phase-ga-u-hcp-a3); _phase:ga-u:hcp-a3_ | Mg · A3 · hP2 · P6_3/mmc (194) | tier A: standard phase name | not stable in 2 calculated diagram(s) | 0 | 2 |
| [LIQUID](#phase-ga-u-liquid); _phase:ga-u:liquid_ | liquid | liquid | stable in 2 of 2 calculated diagram(s): 302.91–4000 K, x(U) 0–1 | 18 | 2 |
| [TETRAGONAL_U](#phase-ga-u-u-tetragonal); _phase:ga-u:u-tetragonal_ |  | needs_review | stable in 2 of 2 calculated diagram(s): 925.77–1048.28 K, x(U) 0.98871–1 | 7 | 2 |

## ORTHORHOMBIC_A11 (Ga–U)

- Id: `phase:ga-u:a11-orthorhombic`; status `assigned`
- Structure: alpha-Ga · A11 · oC8 · Cmce (64); type `st:a11-alpha-ga-oc8`; tier A: standard phase name; confidence high
- Stability: stable in 2 of 2 calculated diagram(s): 300–940 K, x(U) 0–1
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:ga-u:a11-orthorhombic)

Names (3): _corpus: _corpus:phase:ga-u:a11-orthorhombic  
_tdb: _tdb:GaU-08Wan.tdb:ORTHORHOMBIC_A11, tdb:GaU-18Mou.tdb:ORTHORHOMBIC_A11  


### TDB models of ORTHORHOMBIC_A11 (2): PHASE and CONSTITUENT statements as written

[GaU-08Wan.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-08Wan.tdb): ORTHORHOMBIC_A11, type code %, sha256 `e761d0dee84952be…`

~~~~text
43: PHASE ORTHORHOMBIC_A11 % 1 1 !
44: CONST ORTHORHOMBIC_A11 : GA% U : !
~~~~

[GaU-18Mou.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-18Mou.tdb): ORTHORHOMBIC_A11, type code %, sha256 `f541e5cb65bafef3…`

~~~~text
44: PHASE ORTHORHOMBIC_A11 % 1 1 !
45: CONST ORTHORHOMBIC_A11 : GA% U : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/j.jnucmat.2008.07.009](https://doi.org/10.1016/j.jnucmat.2008.07.009) J. Wang, X.J. Liu, C.P. Wang, Thermodynamic calculation of phase equilibria of the U–Ga and U–W systems, Journal of Nuclear Materials 380, 105-110 (2008).  
_assessment that models this phase_
- [doi:10.1016/j.jnucmat.2017.11.037](https://doi.org/10.1016/j.jnucmat.2017.11.037) Chantal Moussa, Alexandre Berche, José Barbosa, Mathieu Pasturel, Bertrand Stepnik, Olivier Tougait, Experimental investigation of the phase equilibria and thermodynamic assessment in the U-Ga and U-Al-Ga systems, Journal of Nuclear Materials 499, 361-371 (2018).  
_assessment that models this phase_

## ORTHORHOMBIC_A20 (Ga–U)

- Id: `phase:ga-u:a20-orthorhombic`; status `assigned`
- Structure: alpha-U · A20 · oC4 · Cmcm (63); type `st:a20-alpha-u-oc4`; tier A: standard phase name; confidence high
- Stability: stable in 2 of 2 calculated diagram(s): 300–1048.28 K, x(U) 0–1
- Literature: 6 values (6 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:ga-u:a20-orthorhombic)

Names (5): _corpus: _corpus:phase:ga-u:a20-orthorhombic, corpus:phase:ga-u:orthorhombic-a20  
_paper: _paper:10.1016/j.jnucmat.2017.11.037:αU  
_tdb: _tdb:GaU-08Wan.tdb:ORTHORHOMBIC_A20, tdb:GaU-18Mou.tdb:ORTHORHOMBIC_A20  


### TDB models of ORTHORHOMBIC_A20 (2): PHASE and CONSTITUENT statements as written

[GaU-08Wan.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-08Wan.tdb): ORTHORHOMBIC_A20, type code %, sha256 `e761d0dee84952be…`

~~~~text
48: PHASE ORTHORHOMBIC_A20 % 1 1 !
49: CONST ORTHORHOMBIC_A20 : GA U% : !
~~~~

[GaU-18Mou.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-18Mou.tdb): ORTHORHOMBIC_A20, type code %, sha256 `f541e5cb65bafef3…`

~~~~text
49: PHASE ORTHORHOMBIC_A20 % 1 1 !
50: CONST ORTHORHOMBIC_A20 : GA U% : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/j.jnucmat.2017.11.037](https://doi.org/10.1016/j.jnucmat.2017.11.037) Chantal Moussa, Alexandre Berche, José Barbosa, Mathieu Pasturel, Bertrand Stepnik, Olivier Tougait, Experimental investigation of the phase equilibria and thermodynamic assessment in the U-Ga and U-Al-Ga systems, Journal of Nuclear Materials 499, 361-371 (2018).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.jnucmat.2008.07.009](https://doi.org/10.1016/j.jnucmat.2008.07.009) J. Wang, X.J. Liu, C.P. Wang, Thermodynamic calculation of phase equilibria of the U–Ga and U–W systems, Journal of Nuclear Materials 380, 105-110 (2008).  
_assessment that models this phase_

## BCC_A2 (Ga–U)

- Id: `phase:ga-u:bcc-a2`; status `assigned`
- Structure: W · A2 · cI2 · Im-3m (229); type `st:a2-w-ci2`; tier A: standard phase name; confidence high
- Stability: stable in 2 of 2 calculated diagram(s): 1006.58–1408.98 K, x(U) 0.9078–1
- Literature: 7 values (7 accepted) from 2 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:ga-u:bcc-a2)

Names (5): _corpus: _corpus:phase:ga-u:bcc-a2  
_paper: _paper:10.1016/j.jnucmat.2008.07.009:γ (U), paper:10.1016/j.jnucmat.2017.11.037:γU  
_tdb: _tdb:GaU-08Wan.tdb:BCC_A2, tdb:GaU-18Mou.tdb:BCC_A2  


### TDB models of BCC_A2 (2): PHASE and CONSTITUENT statements as written

[GaU-08Wan.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-08Wan.tdb): BCC_A2, type code %B, sha256 `e761d0dee84952be…`

~~~~text
33: PHASE BCC_A2 %B 2 1 3 !
34: CONST BCC_A2 : GA U% : VA : !
~~~~

[GaU-18Mou.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-18Mou.tdb): BCC_A2, type code %B, sha256 `f541e5cb65bafef3…`

~~~~text
34: PHASE BCC_A2 %B 2 1 3 !
35: CONST BCC_A2 : GA U% : VA : !
~~~~

Example references (3 of 3; assessments first): 

- [doi:10.1016/j.jnucmat.2008.07.009](https://doi.org/10.1016/j.jnucmat.2008.07.009) J. Wang, X.J. Liu, C.P. Wang, Thermodynamic calculation of phase equilibria of the U–Ga and U–W systems, Journal of Nuclear Materials 380, 105-110 (2008).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.jnucmat.2017.11.037](https://doi.org/10.1016/j.jnucmat.2017.11.037) Chantal Moussa, Alexandre Berche, José Barbosa, Mathieu Pasturel, Bertrand Stepnik, Olivier Tougait, Experimental investigation of the phase equilibria and thermodynamic assessment in the U-Ga and U-Al-Ga systems, Journal of Nuclear Materials 499, 361-371 (2018).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90140-9](https://doi.org/10.1016/0022-5088%2873%2990140-9) K.H.J. Buschow, Phase relationships and magnetic properties of uranium-gallium compounds, Journal of the Less Common Metals 31, 165-168 (1973).  
_cited as the source of values for this phase_

## FCC_A1 (Ga–U)

- Id: `phase:ga-u:fcc-a1`; status `assigned`
- Structure: Cu · A1 · cF4 · Fm-3m (225); type `st:a1-cu-cf4`; tier A: standard phase name; confidence high
- Stability: not stable in 2 calculated diagram(s)
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:ga-u:fcc-a1)

Names (3): _corpus: _corpus:phase:ga-u:fcc-a1  
_tdb: _tdb:GaU-08Wan.tdb:FCC_A1, tdb:GaU-18Mou.tdb:FCC_A1  


### TDB models of FCC_A1 (2): PHASE and CONSTITUENT statements as written

[GaU-08Wan.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-08Wan.tdb): FCC_A1, type code %A, sha256 `e761d0dee84952be…`

~~~~text
28: PHASE FCC_A1 %A 2 1 1 !
29: CONST FCC_A1 : GA U : VA : !
~~~~

[GaU-18Mou.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-18Mou.tdb): FCC_A1, type code %A, sha256 `f541e5cb65bafef3…`

~~~~text
29: PHASE FCC_A1 %A 2 1 1 !
30: CONST FCC_A1 : GA U : VA : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/j.jnucmat.2008.07.009](https://doi.org/10.1016/j.jnucmat.2008.07.009) J. Wang, X.J. Liu, C.P. Wang, Thermodynamic calculation of phase equilibria of the U–Ga and U–W systems, Journal of Nuclear Materials 380, 105-110 (2008).  
_assessment that models this phase_
- [doi:10.1016/j.jnucmat.2017.11.037](https://doi.org/10.1016/j.jnucmat.2017.11.037) Chantal Moussa, Alexandre Berche, José Barbosa, Mathieu Pasturel, Bertrand Stepnik, Olivier Tougait, Experimental investigation of the phase equilibria and thermodynamic assessment in the U-Ga and U-Al-Ga systems, Journal of Nuclear Materials 499, 361-371 (2018).  
_assessment that models this phase_

## GA2U_C32 (Ga–U)

- Id: `phase:ga-u:ga2u-c32`; status `assigned`
- Structure: AlB2 · C32 · hP3 · P6/mmm (191); type `st:c32-alb2-hp3`; tier A: standard phase name; confidence high
- Stoichiometry: Ga 0.6667, U 0.3333
- Stability: stable in 2 of 2 calculated diagram(s): 300–1659.6 K, x(U) 0.33333–0.33333
- Literature: 10 values (10 accepted) from 2 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:ga-u:ga2u-c32)

Names (5): _corpus: _corpus:phase:ga-u:ga2u-c32  
_paper: _paper:10.1016/j.jnucmat.2008.07.009:Ga2U, paper:10.1016/j.jnucmat.2017.11.037:UGa2  
_tdb: _tdb:GaU-08Wan.tdb:GA2U_C32, tdb:GaU-18Mou.tdb:GA2U_C32  


### TDB models of GA2U_C32 (2): PHASE and CONSTITUENT statements as written

[GaU-08Wan.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-08Wan.tdb): GA2U_C32, type code %, sha256 `e761d0dee84952be…`

~~~~text
63: PHASE GA2U_C32 % 2 2 1 !
64: CONST GA2U_C32 : GA : U : !
~~~~

[GaU-18Mou.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-18Mou.tdb): GA2U_C32, type code %, sha256 `f541e5cb65bafef3…`

~~~~text
64: PHASE GA2U_C32 % 2 2 1 !
65: CONST GA2U_C32 : GA : U : !
~~~~

Example references (3 of 3; assessments first): 

- [doi:10.1016/j.jnucmat.2008.07.009](https://doi.org/10.1016/j.jnucmat.2008.07.009) J. Wang, X.J. Liu, C.P. Wang, Thermodynamic calculation of phase equilibria of the U–Ga and U–W systems, Journal of Nuclear Materials 380, 105-110 (2008).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.jnucmat.2017.11.037](https://doi.org/10.1016/j.jnucmat.2017.11.037) Chantal Moussa, Alexandre Berche, José Barbosa, Mathieu Pasturel, Bertrand Stepnik, Olivier Tougait, Experimental investigation of the phase equilibria and thermodynamic assessment in the U-Ga and U-Al-Ga systems, Journal of Nuclear Materials 499, 361-371 (2018).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90140-9](https://doi.org/10.1016/0022-5088%2873%2990140-9) K.H.J. Buschow, Phase relationships and magnetic properties of uranium-gallium compounds, Journal of the Less Common Metals 31, 165-168 (1973).  
_cited as the source of values for this phase_

## GA3U_L12 (Ga–U)

- Id: `phase:ga-u:ga3u-l12`; status `assigned`
- Structure: AuCu3 · L1_2 · cP4 · Pm-3m (221); type `st:l1-2-aucu3-cp4`; tier A: standard phase name; confidence high
- Caveat: DFT agrees: on-hull mp-aaaabdxm and oqmd-30363, space group 221
- Stoichiometry: Ga 0.7500, U 0.2500
- Stability: stable in 2 of 2 calculated diagram(s): 300–1556.93 K, x(U) 0.25–0.25
- Literature: 3 values (3 accepted) from 2 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:ga-u:ga3u-l12)

Names (7): _corpus: _corpus:phase:ga-u:ga3u-l12  
_mp: _mp:mp-aaaabdxm  
_oqmd: _oqmd:oqmd-30363  
_paper: _paper:10.1016/j.jnucmat.2008.07.009:Ga3U, paper:10.1016/j.jnucmat.2017.11.037:UGa3  
_tdb: _tdb:GaU-08Wan.tdb:GA3U_L12, tdb:GaU-18Mou.tdb:GA3U_L12  


### TDB models of GA3U_L12 (2): PHASE and CONSTITUENT statements as written

[GaU-08Wan.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-08Wan.tdb): GA3U_L12, type code %, sha256 `e761d0dee84952be…`

~~~~text
58: PHASE GA3U_L12 % 2 3 1 !
59: CONST GA3U_L12 : GA : U : !
~~~~

[GaU-18Mou.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-18Mou.tdb): GA3U_L12, type code %, sha256 `f541e5cb65bafef3…`

~~~~text
59: PHASE GA3U_L12 % 2 3 1 !
60: CONST GA3U_L12 : GA : U : !
~~~~

Example references (3 of 3; assessments first): 

- [doi:10.1016/j.jnucmat.2008.07.009](https://doi.org/10.1016/j.jnucmat.2008.07.009) J. Wang, X.J. Liu, C.P. Wang, Thermodynamic calculation of phase equilibria of the U–Ga and U–W systems, Journal of Nuclear Materials 380, 105-110 (2008).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.jnucmat.2017.11.037](https://doi.org/10.1016/j.jnucmat.2017.11.037) Chantal Moussa, Alexandre Berche, José Barbosa, Mathieu Pasturel, Bertrand Stepnik, Olivier Tougait, Experimental investigation of the phase equilibria and thermodynamic assessment in the U-Ga and U-Al-Ga systems, Journal of Nuclear Materials 499, 361-371 (2018).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90140-9](https://doi.org/10.1016/0022-5088%2873%2990140-9) K.H.J. Buschow, Phase relationships and magnetic properties of uranium-gallium compounds, Journal of the Less Common Metals 31, 165-168 (1973).  
_cited as the source of values for this phase_

## GA3U2 (Ga–U)

- Id: `phase:ga-u:ga3u2`; status `assigned`
- Structure: Pd5Pu3 · oC32 · Cmcm (63); type `st:pd5pu3-oc32`; tier C: assessor-stated (Hallstedt 2025 crystallographic table); confidence assessor-stated
- Structure source: B. Hallstedt, The SGTE collection of binary datasets, Calphad 89 (2025) 102833, supplementary crystallographic table (mmc2) [doi:10.1016/j.calphad.2025.102833](https://doi.org/10.1016/j.calphad.2025.102833)
- Caveat: not certain from the name or DFT alone (no_on_hull_entry_in_both, no_structure_token); structure as stated in the SGTE crystallographic table for this phase name and system
- Stoichiometry: Ga 0.6000, U 0.4000
- Stability: stable in 1 of 1 calculated diagram(s): 300–1532.19 K, x(U) 0.4–0.4
- Literature: 8 values (8 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:ga-u:ga3u2)

Names (3): _corpus: _corpus:phase:ga-u:ga3u2  
_paper: _paper:10.1016/j.jnucmat.2008.07.009:Ga3U2  
_tdb: _tdb:GaU-08Wan.tdb:GA3U2  


### TDB models of GA3U2 (1): PHASE and CONSTITUENT statements as written

[GaU-08Wan.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-08Wan.tdb): GA3U2, type code %, sha256 `e761d0dee84952be…`

~~~~text
68: PHASE GA3U2 % 2 3 2 !
69: CONST GA3U2 : GA : U : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/j.jnucmat.2008.07.009](https://doi.org/10.1016/j.jnucmat.2008.07.009) J. Wang, X.J. Liu, C.P. Wang, Thermodynamic calculation of phase equilibria of the U–Ga and U–W systems, Journal of Nuclear Materials 380, 105-110 (2008).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90140-9](https://doi.org/10.1016/0022-5088%2873%2990140-9) K.H.J. Buschow, Phase relationships and magnetic properties of uranium-gallium compounds, Journal of the Less Common Metals 31, 165-168 (1973).  
_cited as the source of values for this phase_

## GA5U3 (Ga–U)

- Id: `phase:ga-u:ga5u3`; status `needs_review`
- No structure assigned. Why: no_on_hull_entry_in_both; no_structure_token
- Candidate (tdb_comment): Pd5Pu3 · oC32 · Cmcm — GaU-18Mou.tdb: 'Prototype Pd5Pu3 (oC32, Cmcm)'
- Stoichiometry: Ga 0.6250, U 0.3750
- Stability: stable in 1 of 1 calculated diagram(s): 300–1535.71 K, x(U) 0.375–0.375
- Literature: 4 values (4 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:ga-u:ga5u3)

Names (3): _corpus: _corpus:phase:ga-u:ga5u3  
_paper: _paper:10.1016/j.jnucmat.2017.11.037:U3Ga5  
_tdb: _tdb:GaU-18Mou.tdb:GA5U3  


### TDB models of GA5U3 (1): PHASE and CONSTITUENT statements as written

[GaU-18Mou.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-18Mou.tdb): GA5U3, type code %, sha256 `f541e5cb65bafef3…`

~~~~text
69: PHASE GA5U3 % 2 5 3 !
70: CONST GA5U3 : GA : U : !
~~~~

Example references (1 of 1; assessments first): 

- [doi:10.1016/j.jnucmat.2017.11.037](https://doi.org/10.1016/j.jnucmat.2017.11.037) Chantal Moussa, Alexandre Berche, José Barbosa, Mathieu Pasturel, Bertrand Stepnik, Olivier Tougait, Experimental investigation of the phase equilibria and thermodynamic assessment in the U-Ga and U-Al-Ga systems, Journal of Nuclear Materials 499, 361-371 (2018).  
_assessment that models this phase; reports values for this phase_

## HCP_A3 (Ga–U)

- Id: `phase:ga-u:hcp-a3`; status `assigned`
- Structure: Mg · A3 · hP2 · P6_3/mmc (194); type `st:a3-mg-hp2`; tier A: standard phase name; confidence high
- Stability: not stable in 2 calculated diagram(s)
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:ga-u:hcp-a3)

Names (3): _corpus: _corpus:phase:ga-u:hcp-a3  
_tdb: _tdb:GaU-08Wan.tdb:HCP_A3, tdb:GaU-18Mou.tdb:HCP_A3  


### TDB models of HCP_A3 (2): PHASE and CONSTITUENT statements as written

[GaU-08Wan.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-08Wan.tdb): HCP_A3, type code %A, sha256 `e761d0dee84952be…`

~~~~text
38: PHASE HCP_A3 %A 2 1 0.5 !
39: CONST HCP_A3 : GA U : VA : !
~~~~

[GaU-18Mou.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-18Mou.tdb): HCP_A3, type code %A, sha256 `f541e5cb65bafef3…`

~~~~text
39: PHASE HCP_A3 %A 2 1 0.5 !
40: CONST HCP_A3 : GA U : VA : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/j.jnucmat.2008.07.009](https://doi.org/10.1016/j.jnucmat.2008.07.009) J. Wang, X.J. Liu, C.P. Wang, Thermodynamic calculation of phase equilibria of the U–Ga and U–W systems, Journal of Nuclear Materials 380, 105-110 (2008).  
_assessment that models this phase_
- [doi:10.1016/j.jnucmat.2017.11.037](https://doi.org/10.1016/j.jnucmat.2017.11.037) Chantal Moussa, Alexandre Berche, José Barbosa, Mathieu Pasturel, Bertrand Stepnik, Olivier Tougait, Experimental investigation of the phase equilibria and thermodynamic assessment in the U-Ga and U-Al-Ga systems, Journal of Nuclear Materials 499, 361-371 (2018).  
_assessment that models this phase_

## LIQUID (Ga–U)

- Id: `phase:ga-u:liquid`; status `assigned`
- Structure: liquid; type `st:liquid`; liquid; confidence high
- Stability: stable in 2 of 2 calculated diagram(s): 302.91–4000 K, x(U) 0–1
- Literature: 18 values (18 accepted) from 2 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:ga-u:liquid)

Names (5): _corpus: _corpus:phase:ga-u:liquid  
_paper: _paper:10.1016/j.jnucmat.2008.07.009:L, paper:10.1016/j.jnucmat.2017.11.037:L  
_tdb: _tdb:GaU-08Wan.tdb:LIQUID, tdb:GaU-18Mou.tdb:LIQUID  


### TDB models of LIQUID (2): PHASE and CONSTITUENT statements as written

[GaU-08Wan.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-08Wan.tdb): LIQUID, type code %, sha256 `e761d0dee84952be…`

~~~~text
23: PHASE LIQUID:L % 1 1 !
24: CONST LIQUID:L : GA U : !
~~~~

[GaU-18Mou.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-18Mou.tdb): LIQUID, type code %, sha256 `f541e5cb65bafef3…`

~~~~text
24: PHASE LIQUID:L % 1 1 !
25: CONST LIQUID:L : GA U : !
~~~~

Example references (3 of 3; assessments first): 

- [doi:10.1016/j.jnucmat.2017.11.037](https://doi.org/10.1016/j.jnucmat.2017.11.037) Chantal Moussa, Alexandre Berche, José Barbosa, Mathieu Pasturel, Bertrand Stepnik, Olivier Tougait, Experimental investigation of the phase equilibria and thermodynamic assessment in the U-Ga and U-Al-Ga systems, Journal of Nuclear Materials 499, 361-371 (2018).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.jnucmat.2008.07.009](https://doi.org/10.1016/j.jnucmat.2008.07.009) J. Wang, X.J. Liu, C.P. Wang, Thermodynamic calculation of phase equilibria of the U–Ga and U–W systems, Journal of Nuclear Materials 380, 105-110 (2008).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90140-9](https://doi.org/10.1016/0022-5088%2873%2990140-9) K.H.J. Buschow, Phase relationships and magnetic properties of uranium-gallium compounds, Journal of the Less Common Metals 31, 165-168 (1973).  
_cited as the source of values for this phase_

## TETRAGONAL_U (Ga–U)

- Id: `phase:ga-u:u-tetragonal`; status `needs_review`
- No structure assigned. Why: name_has_descriptive_tokens:TETRAGONAL; no_structure_token
- Candidate (sgte_mmc2): beta-U · A_b · tP30 · P4_2/mnm (136) — Hallstedt 2025 mmc2 row for TETRAGONAL_U: beta-U
- Candidate (tdb_comment): beta-U · tP30 · P4_2/mnm, SB: A_b — GaU-08Wan.tdb: 'Prototype beta-U (tP30, P4_2/mnm, SB: A_b)'
- Candidate (tdb_comment): beta-U · tP30 · P4_2/mnm, SB: A_b — GaU-18Mou.tdb: 'Prototype beta-U (tP30, P4_2/mnm, SB: A_b)'
- Stability: stable in 2 of 2 calculated diagram(s): 925.77–1048.28 K, x(U) 0.98871–1
- Literature: 7 values (7 accepted) from 2 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:ga-u:u-tetragonal)

Names (6): _corpus: _corpus:phase:ga-u:u-tetragonal, corpus:phase:ga-u:tetragonal-u  
_paper: _paper:10.1016/j.jnucmat.2008.07.009:β (U), paper:10.1016/j.jnucmat.2017.11.037:βU  
_tdb: _tdb:GaU-08Wan.tdb:TETRAGONAL_U, tdb:GaU-18Mou.tdb:TETRAGONAL_U  


### TDB models of TETRAGONAL_U (2): PHASE and CONSTITUENT statements as written

[GaU-08Wan.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-08Wan.tdb): TETRAGONAL_U, type code %, sha256 `e761d0dee84952be…`

~~~~text
53: PHASE TETRAGONAL_U % 1 1 !
54: CONST TETRAGONAL_U : GA U% : !
~~~~

[GaU-18Mou.tdb](https://orchid-project.org/data/databases/sgte-binary/GaU-18Mou.tdb): TETRAGONAL_U, type code %, sha256 `f541e5cb65bafef3…`

~~~~text
54: PHASE TETRAGONAL_U % 1 1 !
55: CONST TETRAGONAL_U : GA U% : !
~~~~

Example references (3 of 3; assessments first): 

- [doi:10.1016/j.jnucmat.2008.07.009](https://doi.org/10.1016/j.jnucmat.2008.07.009) J. Wang, X.J. Liu, C.P. Wang, Thermodynamic calculation of phase equilibria of the U–Ga and U–W systems, Journal of Nuclear Materials 380, 105-110 (2008).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.jnucmat.2017.11.037](https://doi.org/10.1016/j.jnucmat.2017.11.037) Chantal Moussa, Alexandre Berche, José Barbosa, Mathieu Pasturel, Bertrand Stepnik, Olivier Tougait, Experimental investigation of the phase equilibria and thermodynamic assessment in the U-Ga and U-Al-Ga systems, Journal of Nuclear Materials 499, 361-371 (2018).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90140-9](https://doi.org/10.1016/0022-5088%2873%2990140-9) K.H.J. Buschow, Phase relationships and magnetic properties of uranium-gallium compounds, Journal of the Less Common Metals 31, 165-168 (1973).  
_cited as the source of values for this phase_

## Please cite

- R. Arróyave, J. Saal, D. Shin, ORCHID-Registry: phase registry of binary systems (version 2026.10; Version 1, machine-extracted), Zenodo (2026). https://doi.org/10.5281/zenodo.23735970
- 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 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); the original source of every value you use (paper_citation / paper_doi, and cited_dois for values the paper cites from earlier work).

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_phase_registry_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Registry: phase registry of binary systems}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735970},
  url       = {https://doi.org/10.5281/zenodo.23735970},
  note      = {Version 1, machine-extracted}
}

@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 the ORCHID phase registry and the sources named on the page (TDB assessments, Hallstedt 2025, Materials Project, OQMD). TDB statements are quoted as written; parameter expressions are not reproduced. Field reference: [SCHEMA.md](https://data.orchid-project.org/phases/SCHEMA.md). Machine-readable guide: [llms.txt](https://data.orchid-project.org/llms.txt).