Basic Thermodynamics of Protein-Ligand Interactions

Thermodynamics, originally the study of the more limited phenomena of heat and heat transfer, evolved to become the more broad study of energy and energy transfer with the recognition - through the cumulative work of Count Rumford 

Protein-Ligand Interactions From Molecular Recognition to Drug Design. 

Copyright 2003 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim 

The First Law of fhermodynamics (colloquially, the law of conservation of energy Mayer, Helmholtz) does not explain why or guarantee that a defined system change will occur spontaneously or, if it does, in which direction the change will occur. This shortcoming is addressed by the Second Law of fhermodynamics. Again, a vast amount of experience and experimentation can be generahzed by (Carnot, Kelvin, Clausius), 

1) U (or ) was previously teniied the internal energy (no longer used). For a closed system (defined as one in which there is no exchange of mass with the sunoundings ) at rest, A(7=Q+ W if there is no other mechanism of exchange of energy. By convention, 

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