# Si–Y phases

> Si–Y system: 12 phases (tier A 8, tier C 2, liquid 1, needs_review 1); 11 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/SI-Y.html · Markdown: https://data.orchid-project.org/phases/pages/SI-Y.md

12 phases (tier A 8, tier C 2, liquid 1, needs_review 1); 11 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=SI-Y) · [full JSON](https://data.orchid-project.org/phases/systems/SI-Y.json) · [Si–Y system page](https://data.orchid-project.org/systems/SI-Y.html) · [Markdown](https://data.orchid-project.org/phases/pages/SI-Y.md) · [field reference](https://data.orchid-project.org/phases/SCHEMA.md)

Table: Phases of the Si–Y system (12)

| Phase | Structure | Basis | Stability (calculated) | Literature values | TDB models |
|---|---|---|---|---:|---:|
| [DIAMOND_A4](#phase-si-y-a4-diamond); _phase:si-y:a4-diamond_ | C (diamond) · A4 · cF8 · Fd-3m (227) | tier A: standard phase name | stable in 4 of 4 calculated diagram(s): 300–1707.23 K, x(Y) 0–0 | 0 | 4 |
| [BCC_A2](#phase-si-y-bcc-a2); _phase:si-y:bcc-a2_ | W · A2 · cI2 · Im-3m (229) | tier A: standard phase name | stable in 4 of 4 calculated diagram(s): 526.15–2499.9 K, x(Y) 1–1 | 0 | 4 |
| [FCC_A1](#phase-si-y-fcc-a1); _phase:si-y:fcc-a1_ | Cu · A1 · cF4 · Fm-3m (225) | tier A: standard phase name | not stable in 4 calculated diagram(s) | 0 | 4 |
| [HCP_A3](#phase-si-y-hcp-a3); _phase:si-y:hcp-a3_ | Mg · A3 · hP2 · P6_3/mmc (194) | tier A: standard phase name | stable in 4 of 4 calculated diagram(s): 300–1751.15 K, x(Y) 1–1 | 0 | 4 |
| [LIQUID](#phase-si-y-liquid); _phase:si-y:liquid_ | liquid | liquid | stable in 4 of 4 calculated diagram(s): 1478.48–2500 K, x(Y) 0–1 | 0 | 4 |
| [SI2Y_C32](#phase-si-y-si2y-c32); _phase:si-y:si2y-c32_ | AlB2 · C32 · hP3 · P6/mmm (191) | tier A: standard phase name | stable in 4 of 4 calculated diagram(s): 300–1527.15 K, x(Y) 0.32822–0.33953 | 0 | 4 |
| [SI2Y_CC](#phase-si-y-si2y-cc); _phase:si-y:si2y-cc_ | Si2Th · C_c · tI12 · I4_1/amd (141) | tier A: standard phase name | stable in 4 of 4 calculated diagram(s): 1523–1795.92 K, x(Y) 0.33002–0.34515 | 0 | 4 |
| [SI3Y5_D88](#phase-si-y-si3y5-d88); _phase:si-y:si3y5-d88_ | Mn5Si3 · D8_8 · hP16 · P6_3/mcm (193) | tier A: standard phase name | stable in 4 of 4 calculated diagram(s): 300–2146.03 K, x(Y) 0.625–0.63731 | 0 | 4 |
| [SI4Y5](#phase-si-y-si4y5); _phase:si-y:si4y5_ | Gd5Si4 · oP36 · Pnma (62) | tier C: assessor-stated (Hallstedt 2025 crystallographic table) | stable in 4 of 4 calculated diagram(s): 300–2144.02 K, x(Y) 0.55556–0.55556 | 0 | 4 |
| [SI5Y3_RT](#phase-si-y-si5y3); _phase:si-y:si5y3_ | GdSi1.4 · oI12 · Imma (74) | tier C: assessor-stated (Hallstedt 2025 crystallographic table) | stable in 4 of 4 calculated diagram(s): 300–723.55 K, x(Y) 0.375–0.375 | 0 | 4 |
| [SI5Y3_C32](#phase-si-y-si5y3-c32); _phase:si-y:si5y3-c32_ |  | needs_review | stable in 4 of 4 calculated diagram(s): 723–1915.13 K, x(Y) 0.375–0.375 | 0 | 4 |
| [SIY_B33](#phase-si-y-siy-b33); _phase:si-y:siy-b33_ | CrB · B33 · oC8 · Cmcm (63) | tier A: standard phase name | stable in 4 of 4 calculated diagram(s): 300–2111.17 K, x(Y) 0.5–0.5 | 0 | 4 |

## DIAMOND_A4 (Si–Y)

- Id: `phase:si-y:a4-diamond`; status `assigned`
- Structure: C (diamond) · A4 · cF8 · Fd-3m (227); type `st:a4-c-diamond-cf8`; tier A: standard phase name; confidence high
- Stoichiometry: Si 1.0000
- Stability: stable in 4 of 4 calculated diagram(s): 300–1707.23 K, x(Y) 0–0
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:si-y:a4-diamond)

Names (5): _corpus: _corpus:phase:si-y:a4-diamond  
_tdb: _tdb:SiY-04Luk-LB.tdb:DIAMOND_A4, tdb:SiY-19Xu.tdb:DIAMOND_A4, tdb:SiY-19Zha.tdb:DIAMOND_A4, tdb:SiY-98Luk.tdb:DIAMOND_A4  


### TDB models of DIAMOND_A4 (4): PHASE and CONSTITUENT statements as written

[SiY-04Luk-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-04Luk-LB.tdb): DIAMOND_A4, type code %, sha256 `409dae6616db4eca…`

~~~~text
57: PHASE DIAMOND_A4 % 1 1 !
58: CONST DIAMOND_A4 : SI : !
~~~~

[SiY-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Xu.tdb): DIAMOND_A4, type code %, sha256 `502ed24fae9e21aa…`

~~~~text
47: PHASE DIAMOND_A4 % 1 1 !
48: CONST DIAMOND_A4 : SI : !
~~~~

[SiY-19Zha.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Zha.tdb): DIAMOND_A4, type code %, sha256 `228f328ec4446fa3…`

~~~~text
48: PHASE DIAMOND_A4 % 1 1 !
49: CONST DIAMOND_A4 : SI : !
~~~~

[SiY-98Luk.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-98Luk.tdb): DIAMOND_A4, type code %, sha256 `bae0ca1237ae17fe…`

~~~~text
54: PHASE DIAMOND_A4 % 1 1 !
55: CONST DIAMOND_A4 : SI : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/j.calphad.2019.03.009](https://doi.org/10.1016/j.calphad.2019.03.009) Z. Zhang, M.-Y. Chu, X.-S. Zhao, K. Li, S.-L. Shang, Z.-K. Liu, J.-Y. Shen, Calphad, 65, 282-90(2019).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## BCC_A2 (Si–Y)

- Id: `phase:si-y: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 4 of 4 calculated diagram(s): 526.15–2499.9 K, x(Y) 1–1
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:si-y:bcc-a2)

Names (5): _corpus: _corpus:phase:si-y:bcc-a2  
_tdb: _tdb:SiY-04Luk-LB.tdb:BCC_A2, tdb:SiY-19Xu.tdb:BCC_A2, tdb:SiY-19Zha.tdb:BCC_A2, tdb:SiY-98Luk.tdb:BCC_A2  


### TDB models of BCC_A2 (4): PHASE and CONSTITUENT statements as written

[SiY-04Luk-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-04Luk-LB.tdb): BCC_A2, type code %B, sha256 `409dae6616db4eca…`

~~~~text
47: PHASE BCC_A2 %B 2 1 3 !
48: CONST BCC_A2 : SI Y% : VA : !
~~~~

[SiY-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Xu.tdb): BCC_A2, type code %B, sha256 `502ed24fae9e21aa…`

~~~~text
37: PHASE BCC_A2 %B 2 1 3 !
38: CONST BCC_A2 : SI Y% : VA : !
~~~~

[SiY-19Zha.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Zha.tdb): BCC_A2, type code %B, sha256 `228f328ec4446fa3…`

~~~~text
38: PHASE BCC_A2 %B 2 1 3 !
39: CONST BCC_A2 : SI Y% : VA : !
~~~~

[SiY-98Luk.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-98Luk.tdb): BCC_A2, type code %B, sha256 `bae0ca1237ae17fe…`

~~~~text
44: PHASE BCC_A2 %B 2 1 3 !
45: CONST BCC_A2 : SI Y% : VA : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/j.calphad.2019.03.009](https://doi.org/10.1016/j.calphad.2019.03.009) Z. Zhang, M.-Y. Chu, X.-S. Zhao, K. Li, S.-L. Shang, Z.-K. Liu, J.-Y. Shen, Calphad, 65, 282-90(2019).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## FCC_A1 (Si–Y)

- Id: `phase:si-y: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 4 calculated diagram(s)
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:si-y:fcc-a1)

Names (5): _corpus: _corpus:phase:si-y:fcc-a1  
_tdb: _tdb:SiY-04Luk-LB.tdb:FCC_A1, tdb:SiY-19Xu.tdb:FCC_A1, tdb:SiY-19Zha.tdb:FCC_A1, tdb:SiY-98Luk.tdb:FCC_A1  


### TDB models of FCC_A1 (4): PHASE and CONSTITUENT statements as written

[SiY-04Luk-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-04Luk-LB.tdb): FCC_A1, type code %A, sha256 `409dae6616db4eca…`

~~~~text
42: PHASE FCC_A1 %A 2 1 1 !
43: CONST FCC_A1 : SI Y : VA : !
~~~~

[SiY-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Xu.tdb): FCC_A1, type code %A, sha256 `502ed24fae9e21aa…`

~~~~text
32: PHASE FCC_A1 %A 2 1 1 !
33: CONST FCC_A1 : SI Y : VA : !
~~~~

[SiY-19Zha.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Zha.tdb): FCC_A1, type code %A, sha256 `228f328ec4446fa3…`

~~~~text
33: PHASE FCC_A1 %A 2 1 1 !
34: CONST FCC_A1 : SI Y : VA : !
~~~~

[SiY-98Luk.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-98Luk.tdb): FCC_A1, type code %A, sha256 `bae0ca1237ae17fe…`

~~~~text
39: PHASE FCC_A1 %A 2 1 1 !
40: CONST FCC_A1 : SI Y : VA : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/j.calphad.2019.03.009](https://doi.org/10.1016/j.calphad.2019.03.009) Z. Zhang, M.-Y. Chu, X.-S. Zhao, K. Li, S.-L. Shang, Z.-K. Liu, J.-Y. Shen, Calphad, 65, 282-90(2019).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## HCP_A3 (Si–Y)

- Id: `phase:si-y: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: stable in 4 of 4 calculated diagram(s): 300–1751.15 K, x(Y) 1–1
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:si-y:hcp-a3)

Names (5): _corpus: _corpus:phase:si-y:hcp-a3  
_tdb: _tdb:SiY-04Luk-LB.tdb:HCP_A3, tdb:SiY-19Xu.tdb:HCP_A3, tdb:SiY-19Zha.tdb:HCP_A3, tdb:SiY-98Luk.tdb:HCP_A3  


### TDB models of HCP_A3 (4): PHASE and CONSTITUENT statements as written

[SiY-04Luk-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-04Luk-LB.tdb): HCP_A3, type code %A, sha256 `409dae6616db4eca…`

~~~~text
52: PHASE HCP_A3 %A 2 1 0.5 !
53: CONST HCP_A3 : SI Y% : VA : !
~~~~

[SiY-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Xu.tdb): HCP_A3, type code %A, sha256 `502ed24fae9e21aa…`

~~~~text
42: PHASE HCP_A3 %A 2 1 0.5 !
43: CONST HCP_A3 : SI Y% : VA : !
~~~~

[SiY-19Zha.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Zha.tdb): HCP_A3, type code %A, sha256 `228f328ec4446fa3…`

~~~~text
43: PHASE HCP_A3 %A 2 1 0.5 !
44: CONST HCP_A3 : SI Y% : VA : !
~~~~

[SiY-98Luk.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-98Luk.tdb): HCP_A3, type code %A, sha256 `bae0ca1237ae17fe…`

~~~~text
49: PHASE HCP_A3 %A 2 1 0.5 !
50: CONST HCP_A3 : SI Y% : VA : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/j.calphad.2019.03.009](https://doi.org/10.1016/j.calphad.2019.03.009) Z. Zhang, M.-Y. Chu, X.-S. Zhao, K. Li, S.-L. Shang, Z.-K. Liu, J.-Y. Shen, Calphad, 65, 282-90(2019).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## LIQUID (Si–Y)

- Id: `phase:si-y:liquid`; status `assigned`
- Structure: liquid; type `st:liquid`; liquid; confidence high
- Stability: stable in 4 of 4 calculated diagram(s): 1478.48–2500 K, x(Y) 0–1
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:si-y:liquid)

Names (5): _corpus: _corpus:phase:si-y:liquid  
_tdb: _tdb:SiY-04Luk-LB.tdb:LIQUID, tdb:SiY-19Xu.tdb:LIQUID, tdb:SiY-19Zha.tdb:LIQUID, tdb:SiY-98Luk.tdb:LIQUID  


### TDB models of LIQUID (4): PHASE and CONSTITUENT statements as written

[SiY-04Luk-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-04Luk-LB.tdb): LIQUID, type code %, sha256 `409dae6616db4eca…`

~~~~text
37: PHASE LIQUID:L % 1 1 !
38: CONST LIQUID:L : SI Y : !
~~~~

[SiY-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Xu.tdb): LIQUID, type code %, sha256 `502ed24fae9e21aa…`

~~~~text
27: PHASE LIQUID:L % 1 1 !
28: CONST LIQUID:L : SI Y : !
~~~~

[SiY-19Zha.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Zha.tdb): LIQUID, type code %, sha256 `228f328ec4446fa3…`

~~~~text
28: PHASE LIQUID:L % 1 1 !
29: CONST LIQUID:L : SI Y : !
~~~~

[SiY-98Luk.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-98Luk.tdb): LIQUID, type code %, sha256 `bae0ca1237ae17fe…`

~~~~text
34: PHASE LIQUID:L % 1 1 !
35: CONST LIQUID:L : SI Y : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/j.calphad.2019.03.009](https://doi.org/10.1016/j.calphad.2019.03.009) Z. Zhang, M.-Y. Chu, X.-S. Zhao, K. Li, S.-L. Shang, Z.-K. Liu, J.-Y. Shen, Calphad, 65, 282-90(2019).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## SI2Y_C32 (Si–Y)

- Id: `phase:si-y:si2y-c32`; status `assigned`
- Structure: AlB2 · C32 · hP3 · P6/mmm (191); type `st:c32-alb2-hp3`; tier A: standard phase name; confidence high
- Caveat: partitioned order/disorder model in SiY-19Zha.tdb also describes the disordered state
- Stability: stable in 4 of 4 calculated diagram(s): 300–1527.15 K, x(Y) 0.32822–0.33953
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:si-y:si2y-c32)

Names (5): _corpus: _corpus:phase:si-y:si2y-c32  
_tdb: _tdb:SiY-04Luk-LB.tdb:SI2Y_C32, tdb:SiY-19Xu.tdb:SI2Y_C32, tdb:SiY-19Zha.tdb:SI2Y_C32, tdb:SiY-98Luk.tdb:SI2Y_C32  


### TDB models of SI2Y_C32 (4): PHASE and CONSTITUENT statements as written

[SiY-04Luk-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-04Luk-LB.tdb): SI2Y_C32, type code %, sha256 `409dae6616db4eca…`

~~~~text
62: PHASE SI2Y_C32 % 2 2 1 !
63: CONST SI2Y_C32 : SI : Y : !
~~~~

[SiY-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Xu.tdb): SI2Y_C32, type code %, sha256 `502ed24fae9e21aa…`

~~~~text
52: PHASE SI2Y_C32 % 2 2 1 !
53: CONST SI2Y_C32 : SI : Y : !
~~~~

[SiY-19Zha.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Zha.tdb): SI2Y_C32, type code %, sha256 `228f328ec4446fa3…`

~~~~text
53: PHASE SI2Y_C32 % 2 2 1 !
54: CONST SI2Y_C32 : SI% Y : SI Y% : !
~~~~

[SiY-98Luk.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-98Luk.tdb): SI2Y_C32, type code %, sha256 `bae0ca1237ae17fe…`

~~~~text
59: PHASE SI2Y_C32 % 2 2 1 !
60: CONST SI2Y_C32 : SI : Y : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/j.calphad.2019.03.009](https://doi.org/10.1016/j.calphad.2019.03.009) Z. Zhang, M.-Y. Chu, X.-S. Zhao, K. Li, S.-L. Shang, Z.-K. Liu, J.-Y. Shen, Calphad, 65, 282-90(2019).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## SI2Y_CC (Si–Y)

- Id: `phase:si-y:si2y-cc`; status `assigned`
- Structure: Si2Th · C_c · tI12 · I4_1/amd (141); type `st:c-c-si2th-ti12`; tier A: standard phase name; confidence high
- Caveat: partitioned order/disorder model in SiY-19Zha.tdb also describes the disordered state
- Stability: stable in 4 of 4 calculated diagram(s): 1523–1795.92 K, x(Y) 0.33002–0.34515
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:si-y:si2y-cc)

Names (5): _corpus: _corpus:phase:si-y:si2y-cc  
_tdb: _tdb:SiY-04Luk-LB.tdb:SI2Y_CC, tdb:SiY-19Xu.tdb:SI2Y_CC, tdb:SiY-19Zha.tdb:SI2Y_CC, tdb:SiY-98Luk.tdb:SI2Y_CC  


### TDB models of SI2Y_CC (4): PHASE and CONSTITUENT statements as written

[SiY-04Luk-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-04Luk-LB.tdb): SI2Y_CC, type code %, sha256 `409dae6616db4eca…`

~~~~text
67: PHASE SI2Y_CC % 2 2 1 !
68: CONST SI2Y_CC : SI : Y : !
~~~~

[SiY-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Xu.tdb): SI2Y_CC, type code %, sha256 `502ed24fae9e21aa…`

~~~~text
57: PHASE SI2Y_CC % 2 2 1 !
58: CONST SI2Y_CC : SI : Y : !
~~~~

[SiY-19Zha.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Zha.tdb): SI2Y_CC, type code %, sha256 `228f328ec4446fa3…`

~~~~text
58: PHASE SI2Y_CC % 2 2 1 !
59: CONST SI2Y_CC : SI% Y : SI Y% : !
~~~~

[SiY-98Luk.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-98Luk.tdb): SI2Y_CC, type code %, sha256 `bae0ca1237ae17fe…`

~~~~text
64: PHASE SI2Y_CC % 2 2 1 !
65: CONST SI2Y_CC : SI : Y : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/j.calphad.2019.03.009](https://doi.org/10.1016/j.calphad.2019.03.009) Z. Zhang, M.-Y. Chu, X.-S. Zhao, K. Li, S.-L. Shang, Z.-K. Liu, J.-Y. Shen, Calphad, 65, 282-90(2019).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## SI3Y5_D88 (Si–Y)

- Id: `phase:si-y:si3y5-d88`; status `assigned`
- Structure: Mn5Si3 · D8_8 · hP16 · P6_3/mcm (193); type `st:d8-8-mn5si3-hp16`; tier A: standard phase name; confidence high
- Stability: stable in 4 of 4 calculated diagram(s): 300–2146.03 K, x(Y) 0.625–0.63731
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:si-y:si3y5-d88)

Names (5): _corpus: _corpus:phase:si-y:si3y5-d88  
_tdb: _tdb:SiY-04Luk-LB.tdb:SI3Y5_D88, tdb:SiY-19Xu.tdb:SI3Y5_D88, tdb:SiY-19Zha.tdb:SI3Y5_D88, tdb:SiY-98Luk.tdb:SI3Y5_D88  


### TDB models of SI3Y5_D88 (4): PHASE and CONSTITUENT statements as written

[SiY-04Luk-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-04Luk-LB.tdb): SI3Y5_D88, type code %, sha256 `409dae6616db4eca…`

~~~~text
92: PHASE SI3Y5_D88 % 2 3 5 !
93: CONST SI3Y5_D88 : SI : Y : !
~~~~

[SiY-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Xu.tdb): SI3Y5_D88, type code %, sha256 `502ed24fae9e21aa…`

~~~~text
82: PHASE SI3Y5_D88 % 2 3 5 !
83: CONST SI3Y5_D88 : SI : Y : !
~~~~

[SiY-19Zha.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Zha.tdb): SI3Y5_D88, type code %, sha256 `228f328ec4446fa3…`

~~~~text
83: PHASE SI3Y5_D88 % 2 3 5 !
84: CONST SI3Y5_D88 : SI% Y : Y : !
~~~~

[SiY-98Luk.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-98Luk.tdb): SI3Y5_D88, type code %, sha256 `bae0ca1237ae17fe…`

~~~~text
89: PHASE SI3Y5_D88 % 2 3 5 !
90: CONST SI3Y5_D88 : SI : Y : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/j.calphad.2019.03.009](https://doi.org/10.1016/j.calphad.2019.03.009) Z. Zhang, M.-Y. Chu, X.-S. Zhao, K. Li, S.-L. Shang, Z.-K. Liu, J.-Y. Shen, Calphad, 65, 282-90(2019).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## SI4Y5 (Si–Y)

- Id: `phase:si-y:si4y5`; status `assigned`
- Structure: Gd5Si4 · oP36 · Pnma (62); type `st:gd5si4-op36`; 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: Si 0.4444, Y 0.5556
- Stability: stable in 4 of 4 calculated diagram(s): 300–2144.02 K, x(Y) 0.55556–0.55556
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:si-y:si4y5)

Names (5): _corpus: _corpus:phase:si-y:si4y5  
_tdb: _tdb:SiY-04Luk-LB.tdb:SI4Y5, tdb:SiY-19Xu.tdb:SI4Y5, tdb:SiY-19Zha.tdb:SI4Y5, tdb:SiY-98Luk.tdb:SI4Y5  


### TDB models of SI4Y5 (4): PHASE and CONSTITUENT statements as written

[SiY-04Luk-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-04Luk-LB.tdb): SI4Y5, type code %, sha256 `409dae6616db4eca…`

~~~~text
87: PHASE SI4Y5 % 2 4 5 !
88: CONST SI4Y5 : SI : Y : !
~~~~

[SiY-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Xu.tdb): SI4Y5, type code %, sha256 `502ed24fae9e21aa…`

~~~~text
77: PHASE SI4Y5 % 2 4 5 !
78: CONST SI4Y5 : SI : Y : !
~~~~

[SiY-19Zha.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Zha.tdb): SI4Y5, type code %, sha256 `228f328ec4446fa3…`

~~~~text
78: PHASE SI4Y5 % 2 4 5 !
79: CONST SI4Y5 : SI : Y : !
~~~~

[SiY-98Luk.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-98Luk.tdb): SI4Y5, type code %, sha256 `bae0ca1237ae17fe…`

~~~~text
84: PHASE SI4Y5 % 2 4 5 !
85: CONST SI4Y5 : SI : Y : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/j.calphad.2019.03.009](https://doi.org/10.1016/j.calphad.2019.03.009) Z. Zhang, M.-Y. Chu, X.-S. Zhao, K. Li, S.-L. Shang, Z.-K. Liu, J.-Y. Shen, Calphad, 65, 282-90(2019).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## SI5Y3_RT (Si–Y)

- Id: `phase:si-y:si5y3`; status `assigned`
- Structure: GdSi1.4 · oI12 · Imma (74); type `st:gdsi1-4-oi12`; 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_structure_token, polymorph_family:other phases of this system have the same composition); structure as stated in the SGTE crystallographic table for this phase name and system
- Stoichiometry: Si 0.6250, Y 0.3750
- Stability: stable in 4 of 4 calculated diagram(s): 300–723.55 K, x(Y) 0.375–0.375
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:si-y:si5y3)

Names (5): _corpus: _corpus:phase:si-y:si5y3  
_tdb: _tdb:SiY-04Luk-LB.tdb:SI5Y3_RT, tdb:SiY-19Xu.tdb:SI5Y3_RT, tdb:SiY-19Zha.tdb:SI5Y3_RT, tdb:SiY-98Luk.tdb:SI5Y3_RT  


### TDB models of SI5Y3_RT (4): PHASE and CONSTITUENT statements as written

[SiY-04Luk-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-04Luk-LB.tdb): SI5Y3_RT, type code %, sha256 `409dae6616db4eca…`

~~~~text
72: PHASE SI5Y3_RT % 2 5 3 !
73: CONST SI5Y3_RT : SI : Y : !
~~~~

[SiY-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Xu.tdb): SI5Y3_RT, type code %, sha256 `502ed24fae9e21aa…`

~~~~text
62: PHASE SI5Y3_RT % 2 5 3 !
63: CONST SI5Y3_RT : SI : Y : !
~~~~

[SiY-19Zha.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Zha.tdb): SI5Y3_RT, type code %, sha256 `228f328ec4446fa3…`

~~~~text
63: PHASE SI5Y3_RT % 2 5 3 !
64: CONST SI5Y3_RT : SI : Y : !
~~~~

[SiY-98Luk.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-98Luk.tdb): SI5Y3_RT, type code %, sha256 `bae0ca1237ae17fe…`

~~~~text
69: PHASE SI5Y3_RT % 2 5 3 !
70: CONST SI5Y3_RT : SI : Y : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/j.calphad.2019.03.009](https://doi.org/10.1016/j.calphad.2019.03.009) Z. Zhang, M.-Y. Chu, X.-S. Zhao, K. Li, S.-L. Shang, Z.-K. Liu, J.-Y. Shen, Calphad, 65, 282-90(2019).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## SI5Y3_C32 (Si–Y)

- Id: `phase:si-y:si5y3-c32`; status `needs_review`
- No structure assigned. Why: assessment_declared_blocked_by:stoichiometry_contradicts_C32; stoichiometry_contradicts_C32:SiY-04Luk-LB.tdb; stoichiometry_contradicts_C32:SiY-19Xu.tdb; stoichiometry_contradicts_C32:SiY-19Zha.tdb; stoichiometry_contradicts_C32:SiY-98Luk.tdb
- Candidate (dft_oqmd): P-62c (190) — on-hull OQMD Si5 Y3 at x(Y)=0.3750
- Candidate (name_token): AlB2 · C32 · hP3 · P6/mmm (191) — Strukturbericht/word 'C32' in the TDB name
- Candidate (sgte_mmc2): AlB2 · C32 · hP3 · P6/mmm (191) — Hallstedt 2025 mmc2 row for SI5Y3_C32: Si5Y3 (high T)
- Candidate (tdb_comment): AlB2 · hP3 · P6/mmm — SiY-04Luk-LB.tdb: 'Prototype AlB2 (hP3, P6/mmm), high T'
- Candidate (tdb_comment): AlB2 · hP3 · P6/mmm — SiY-19Xu.tdb: 'Prototype AlB2 (hP3, P6/mmm), high T'
- Candidate (tdb_comment): AlB2 · hP3 · P6/mmm — SiY-19Zha.tdb: 'Prototype AlB2 (hP3, P6/mmm), high T'
- Candidate (tdb_comment): AlB2 · hP3 · P6/mmm — SiY-98Luk.tdb: 'Prototype AlB2 (hP3, P6/mmm), high T'
- Stoichiometry: Si 0.6250, Y 0.3750
- Stability: stable in 4 of 4 calculated diagram(s): 723–1915.13 K, x(Y) 0.375–0.375
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:si-y:si5y3-c32)

Names (5): _corpus: _corpus:phase:si-y:si5y3-c32  
_tdb: _tdb:SiY-04Luk-LB.tdb:SI5Y3_C32, tdb:SiY-19Xu.tdb:SI5Y3_C32, tdb:SiY-19Zha.tdb:SI5Y3_C32, tdb:SiY-98Luk.tdb:SI5Y3_C32  


### TDB models of SI5Y3_C32 (4): PHASE and CONSTITUENT statements as written

[SiY-04Luk-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-04Luk-LB.tdb): SI5Y3_C32, type code %, sha256 `409dae6616db4eca…`

~~~~text
77: PHASE SI5Y3_C32 % 2 5 3 !
78: CONST SI5Y3_C32 : SI : Y : !
~~~~

[SiY-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Xu.tdb): SI5Y3_C32, type code %, sha256 `502ed24fae9e21aa…`

~~~~text
67: PHASE SI5Y3_C32 % 2 5 3 !
68: CONST SI5Y3_C32 : SI : Y : !
~~~~

[SiY-19Zha.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Zha.tdb): SI5Y3_C32, type code %, sha256 `228f328ec4446fa3…`

~~~~text
68: PHASE SI5Y3_C32 % 2 5 3 !
69: CONST SI5Y3_C32 : SI : Y : !
~~~~

[SiY-98Luk.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-98Luk.tdb): SI5Y3_C32, type code %, sha256 `bae0ca1237ae17fe…`

~~~~text
74: PHASE SI5Y3_C32 % 2 5 3 !
75: CONST SI5Y3_C32 : SI : Y : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/j.calphad.2019.03.009](https://doi.org/10.1016/j.calphad.2019.03.009) Z. Zhang, M.-Y. Chu, X.-S. Zhao, K. Li, S.-L. Shang, Z.-K. Liu, J.-Y. Shen, Calphad, 65, 282-90(2019).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## SIY_B33 (Si–Y)

- Id: `phase:si-y:siy-b33`; status `assigned`
- Structure: CrB · B33 · oC8 · Cmcm (63); type `st:b33-crb-oc8`; tier A: standard phase name; confidence high
- Stoichiometry: Si 0.5000, Y 0.5000
- Stability: stable in 4 of 4 calculated diagram(s): 300–2111.17 K, x(Y) 0.5–0.5
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:si-y:siy-b33)

Names (5): _corpus: _corpus:phase:si-y:siy-b33  
_tdb: _tdb:SiY-04Luk-LB.tdb:SIY_B33, tdb:SiY-19Xu.tdb:SIY_B33, tdb:SiY-19Zha.tdb:SIY_B33, tdb:SiY-98Luk.tdb:SIY_B33  


### TDB models of SIY_B33 (4): PHASE and CONSTITUENT statements as written

[SiY-04Luk-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-04Luk-LB.tdb): SIY_B33, type code %, sha256 `409dae6616db4eca…`

~~~~text
82: PHASE SIY_B33 % 2 1 1 !
83: CONST SIY_B33 : SI : Y : !
~~~~

[SiY-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Xu.tdb): SIY_B33, type code %, sha256 `502ed24fae9e21aa…`

~~~~text
72: PHASE SIY_B33 % 2 1 1 !
73: CONST SIY_B33 : SI : Y : !
~~~~

[SiY-19Zha.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-19Zha.tdb): SIY_B33, type code %, sha256 `228f328ec4446fa3…`

~~~~text
73: PHASE SIY_B33 % 2 1 1 !
74: CONST SIY_B33 : SI : Y : !
~~~~

[SiY-98Luk.tdb](https://orchid-project.org/data/databases/sgte-binary/SiY-98Luk.tdb): SIY_B33, type code %, sha256 `bae0ca1237ae17fe…`

~~~~text
79: PHASE SIY_B33 % 2 1 1 !
80: CONST SIY_B33 : SI : Y : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/j.calphad.2019.03.009](https://doi.org/10.1016/j.calphad.2019.03.009) Z. Zhang, M.-Y. Chu, X.-S. Zhao, K. Li, S.-L. Shang, Z.-K. Liu, J.-Y. Shen, Calphad, 65, 282-90(2019).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models 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).