Definition
We consider here that a substance changes from a reactant phase to a product phase and that both the phases are in equilibrium at pressure (P) and temperature (T). Clapeyron’s equation expresses the stability relation between the reactant and product phases and gives a dP/dT slope of equilibrium phase boundary between the reactant and the product as a function of P and T. This equation is one of the most important equations for understanding thermodynamic stability relations in geochemical, petrological, and mineralogical processes. For example, when α-quartz SiO2 is in equilibrium with coesite at certain P, T conditions, Clapeyron’s equation gives the slope of the equilibrium quartz-coesite transition boundary in a P-T space where quartz is stable at relatively lower P and higher T and coesite at relatively higher P and lower T.
Clapeyron’s Equation
When reactant and product phases are in equilibrium at P and T, and changes of entropy (ΔS) and volume (ΔV) accompany with the...
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Christensen U (1995) Effects of phase transitions on mantle convection. Annu Rev Earth Planet Sci 23:65–87
Richet P (2001) The physical basis of thermodynamics. Kluwer/Plenum Publishers, New York, 442 pp
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2018 Springer International Publishing AG, part of Springer Nature
About this entry
Cite this entry
Akaogi, M. (2018). Clapeyron’s Equation. In: White, W.M. (eds) Encyclopedia of Geochemistry. Encyclopedia of Earth Sciences Series. Springer, Cham. https://doi.org/10.1007/978-3-319-39312-4_301
Download citation
DOI: https://doi.org/10.1007/978-3-319-39312-4_301
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-39311-7
Online ISBN: 978-3-319-39312-4
eBook Packages: Earth and Environmental ScienceReference Module Physical and Materials ScienceReference Module Earth and Environmental Sciences