Www.factsage.com 1 Data Management in FactSage Sergei A. Decterov École Polytechnique de Montréal.

www.factsage.com1

Data Management in FactSage

Sergei A. Decterov

École Polytechnique de Montréal

2

– Should there be one Repository or several Repositories for different types of systems?• Organics• Alloys• Sulfides• Oxides

– Viable Repository• Sufficiently large• Constantly updated: large amount of data are added

– Format of Repository• Mandatory fields• Recommended fields• Possibility to enter data in free format• It should be easy for authors to add data

Repository of Thermodynamic and Phase Equilibria Data

3

– ID number for each reference• Never changes

– Reference• Chemical Abstracts standard

– Affiliations • It is essential to know the lab for data evaluation

– E-mail• For making inquiries

– Link to the article • Abstract• Is it possible to have a PDF copy?

– References and links to related articles• Description of the experimental method• Studies of the same system by the same group

Bibliographic Database

4

– Who cited this article?• Science Citation Index accessed through the Web of Science• Scopus from Elsevier• Google Scholar• Microsoft Academic

– Blog• Inquiries sent to the authors and their replies• Discussion of data quality• Should not be anonymous?

– Notes and Editorial notes • Brief summary of the data made by any user• Editorial notes made by database managers

– Importance

Bibliographic Database

5

– Elements in alphabetical order• For all studied systems and subsystems

– Search capabilities• Search for a particular system• Search for a particular system with subsystems

– System components• For example CaO-Al2O3-SiO2

– Phases • bcc, fcc for alloys• Major minerals for oxides (feldspar, olivine, pyroxene, etc.)

Studied Chemical System

6

• Calorimetry Calorimitric measurements• CpHT Cp at high temperature (>298 K)• CpLT Cp at low temperature (<298 K)• H-H298 Heat content H(T)-H(298)• Hm Enthalpy of mixing• Hf Enthalpy of formation • Trans Enthalpy and Temperature of Fusion/Transformations

• EMF EMF measurements• Gf Gibbs energy of formation• Act Partial Gibbs energy and/or Activities• TD Thermodynamic properties• Entropy Entropy

• Isopiestic Isopiestic measurements• PO2 Partial Pressure of Oxygen• Pgas Partial Pressures (other than oxygen)• Ptot Total Vapour Pressure

Keywords

7

• PD Phase Diagram• PE Phase Equilibria• Liquidus Liquidus equilibria• Solidus Solidus equilibria• SubSol Subsolidus equilibria• SlbLim Solubility Limit• InvPnt Invariant Points• MisGap Miscibility Gap• Distrib Distributions of minor elements among several phases• Fe2/Fe3 Fe2+/Fe3+ ratios

• Str Crystal Structure Data• LatPar Lattice Parameters• CD Cation Distribution• NonSt Nonstoichiometry, defects (vacancies, etc.)• Ordering Order-disorder transformations; Short-range ordering• Spectr Spectroscopic data

Keywords

8

• Magn Magnetic properties (Tcurie, Tneel, magnetic moment, etc.)• SurfTen Surface Tension• Th-Cond Thermal Conductivity• Visc Viscosity• Diff Diffusion• Kin Kinetic data

• Vol Molar Volume or Density• dV/dP Compressibilities, Bulk Modulus• dV/dT Thermal Expancivities• High-P High Pressure data•• Model Modeling• Opt Optimization• Rev Review• Estim Estimation of Thermodynamic Properties• Exp Experimental methods• Appl Applications of computational thermodynamics

Keywords

9

– Known structure with atomic coordinates• Space Group and Wyckoff Sequence

– Inorganic Crystal Structure Database from FIZ Karlsruhe (Leibniz Institute for Information Infrastructure)

– Depends in some space groups on the choice of origin

• We need to know what phases have related structures– Modeling of several phases as one solution

• May not tell the whole story

– Information on crystal structure is incomplete• What to store?• How to search?

Phase Identification

10

Na2O Al2O3

SiO2 Solid solutions

NaAlO2–based solid solutions

NaAlSiO4–based nepheline and carnegieite solid solutions

Albite, NaAlSi3O8, end-member of multicomponent feldspar

Jadeite, NaAlSi2O6, end-member of multicomponent pyroxene

Na2O-Al2O3-SiO2 system

11

S

N A

Na2O-Al2O3-SiO2 system

Liquid

Nepheline + High Albite (NaAlSi3O8) Quartz (SiO2) + High Albite

- #1196 Weber&Venero'70- SiO2- #1210 Schairer&Bowen'56- #1220 Greig&Barth'38- L+Carn-#1220 Greig&Barth'38- L+Neph-#1220 Greig&Barth'38- Carn-#1220 Greig&Barth'38- Neph-#1220 Greig&Barth'38

NaAlO2 solid solution (1)

NaAlO2s.s.(1)+Carnegieite

Tridymite (SiO2) + High Albite

Liquid+ Tridymite

NaAlSi3O8(s) + SiO2(s2)

Nepheline + Low Albite

NaAlO2 solid solution (2)

NaAlO2 s.s. (1)+Nepheline

NaAlO2 s.s. (2) + Nepheline

Liqu

id+

Cris

toba

lite

1526 (1526)

1119 (1119)

1061 (1062)1081 (1068)

1274

1254 (1254)

490 (490)

867

1465

467 (467)

1865 (1865)

1165

NaAlO2 - SiO2

mole SiO2/(NaAlO2+SiO2)

T(C

)

0 .2 .4 .6 .8 1200

400

600

800

1000

1200

1400

1600

1800

2000

12

Solid Solutions in the NaAlO2-NaAlSiO4 region

13

Feldspar Composes ~60% of the Earth’s crust

One of the most and best studied silicate solid solutions.

The phase transitions are among the most complex

NaAlSi3O8

AlbiteKAlSi3O8

Orthoclase

CaAl2Si2O8

Anorthite

14

Feldspar Structure

Framework silicate

15

Alkali Feldspar

What are the phases?

NaAlSi3O8

AlbiteKAlSi3O8

Orthoclase

16

Alkali Feldspar

Most feldspar minerals and samples are metastable:

Equilibrium long-range ordering is not reached

NaAlSi3O8

AlbiteKAlSi3O8

Orthoclase

C2/mC2/m

CĪ

CĪ

17

Plagioclase Feldspar

NaAlSi3O8

Albite

CaAl2Si2O8

Anorthite

18

Plagioclase Feldspar C1 -> I1 phase transition

Probably 2nd order Different tetrahedral sequences of Al and Si in albite and anorthite

19

Feldspar

− Al-Si ordering is very slow. • Most experimental measurements are made on metastable

samples (not under equilibrium conditions)

• Normally, disordered phases form first

− What database do we need?

• Thermodynamic properties of equilibrium (ordered) feldspars?

• Thermodynamic properties of metastable (more disordered) feldspars that initially form in phase equilibrium measurements?

− How can we identify the studied phase?

• Crystal structure

• Thermal history of samples

20

Information to Store in the Database− Characterization of Samples

• Analysis (before and after the experiment)

• Thermal history

• Crucibles

• Atmosphere

− Unambiguous characterization of the data

• Store primary experimental data (e.g. EMF rather than recalculated thermodynamic properties)

• Units (e.g. pressure in bar or atm)

• Activities, ΔHf with respect to what phases (and at what T )?

• Data used to calculate the reported values

• 1st principles and MD data represent what particular measurable thermodynamic properties and at what conditions?

21

B2O3-SiO2

22

B2O3-SiO2 system

Slag + Quartz(H)

Slag + Tridymite

Slag +

B2O3 + Quartz(L)

Slag

Rockett -1965_Liquid

Rockett -1965_Liq+Sol

Rockett -1965_Solids

Pichavant -1978_Liquid

Pichavant -1978_Liq+Sol

Charles -1968

Cristobalite

Slag + Quartz(L)

The BO1.5 - SiO2 phase diagram

mole fraction SiO2

T(C

)

0.0 0.2 0.4 0.6 0.8 1.0200

400

600

800

1000

1200

1400

1600

1800

2000

23

B2O3-SiO2 system

Enthalpy of mixing in the BO1.5-SiO2 system at 700oC

-10

-9

-8

-7

-6

-5

-4

-3

-2

-1

0

1

2

3

0 0.2 0.4 0.6 0.8 1mole fraction SiO2

Hm

ix, k

J/m

ol

Hervig & Navrotsky, 1985

Calculated

Shul'ts et al., 1986 (25 C)

24

B2O3-SiO2 system

Activity of BO1.5 in the BO1.5-SiO2 melts by mass-spectrometry

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 0.2 0.4 0.6 0.8 1mole fraction SiO2

Ac

tiv

ity

Boike, Hilpert and Muller, 1993 (1202 C)Calculated (1202 C)IdealShul'ts et al., 1986 (1315 C)Activity of SiO2

25

B2O3-SiO2 system

Partial pressure of B2O3 over the BO1.5-SiO2 melts at 1315oC

-5

-4

-3

0 0.2 0.4 0.6 0.8 1mole fraction SiO2

lg [

P(B

2O3)

, atm

]

Calculated

Shul'ts et al., 1986

26

B2O3-SiO2 system

Activities of SiO2 and BO1.5 in the BO1.5-SiO2 melts at 1450oC

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 0.2 0.4 0.6 0.8 1mole fraction SiO2

Ac

tiv

ity

Wang et al., 1996CalculatedIdealActivity SiO2

27

Functionality

− It must be easy to enter data

• Copy and paste the whole table

• Plenty of space for headings

• Impossible to devise a universal set of fields to fill

− Graphs

• Any column of a table versus any other column

• Data from different data sets plotted on the same graph

− Tables that can be copied and paste into Excel • The whole table, not one number at a time

28

Conclusions

− Very few mandatory fields

• Search for a particular system

• Type of data

− Recommended fields

• Not really for search, but to remind what is important

− Enter data in free format • Copy and paste Excel tables