Chalcopyrite(alpha)

Formula : CuFeS2

Family: 
Sulfides
Space group: 
Tetragonal - Scalenohedral HM symbol (4 2m) Space Group: I 42d
Dana class: 
2.9.1.1II- 2 Sulfide Minerals ; 2.9 Sulfides - Including Selenides and Tellurides where Am Bn Xp, with (m+n):p=1:1 ; 2.9.1 Chalcopyrite Group (Tetragonal: I4_2d)
High temperature: 
Its stability range is large from hydrothermal systems to magmatic fluids.
Geological context: 
Common in sulfide veins and disseminated in igneous rocks.

Dernière mise à jour le 25.01.2021

THERMODYNAMICS

Individual properties (298.15 K)
M
g·mol-1
 V°
cm3·mol-1
 ΔGºf
J·mol-1
 ΔHºf
J·mol-1
 Sº
J·mol-1·k-1
 CP
J·mol-1·K-1
183.525 43.900 (Ref.: 95rob/hem) Robie R.A., and Hemingway B.S., 1995. Thermodynamic properties of minerals and related substances at 298.15 K and 1 Bar (105 Pascals) pressure and at higher temperatures. U.S. Geol. Survey Bull., 2131, 461 pp. -194996 (Ref.: Internal calculation) -194900 (Ref.: 95rob/hem) Robie R.A., and Hemingway B.S., 1995. Thermodynamic properties of minerals and related substances at 298.15 K and 1 Bar (105 Pascals) pressure and at higher temperatures. U.S. Geol. Survey Bull., 2131, 461 pp. 124.900 (Ref.: 95rob/hem) Robie R.A., and Hemingway B.S., 1995. Thermodynamic properties of minerals and related substances at 298.15 K and 1 Bar (105 Pascals) pressure and at higher temperatures. U.S. Geol. Survey Bull., 2131, 461 pp. 96.65 (Ref.: 78hel/del,70pan/kin)
CP(T) = a + b·T + ·c·T-2 (T in Kelvin)
a
J·mol-1·K-1
 b * 103
J·mol-1·K-2
 c * 10-5
J·K·mol-1
 Maier Kelley Ref.
86.99 53.56 -5.61 (Ref.: 78hel/del,70pan/kin)
Reaction properties

Chalcopyrite(alpha) + 2H+ ⇌ Cu+2 + Fe+2 + 2HS-

298.15 K, 1 bar log10K: -33.99 ΔH°r:137477 J·mol-1 (Ref.: 95rob/hem) Robie R.A., and Hemingway B.S., 1995. Thermodynamic properties of minerals and related substances at 298.15 K and 1 Bar (105 Pascals) pressure and at higher temperatures. U.S. Geol. Survey Bull., 2131, 461 pp.
T(°C) 0 25 60 100 150 200 250 300
log10K -36.26 -33.99 -31.54 -29.49 -27.71 -26.62 -26.14 -26.34
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
-1924.317049 -0.308115 96811.265163 697.637198 -6113076.415639