Hydration energy calculations

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Hydration energy calculations of some
chemicals and small proteins
1999. 7. 2. By S.J.Kim
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What is the hydration energy?
Hydration energy is the energy of transferring
a molecule from the gas phase into an infinite
bath of water.
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What is the hydration energy?
DG4hyd DG1v,elect DG2c/vdw DG3w,elect
DG1v,elect electrostatic solute-solvent
interaction free energy by discharging the solute
in the first solvent
DG2c/vdw nonpolar or cavity/vdw contribution to
the hydration energy
DG3w,elect associated electrostatic interaction
energy by solute is recharged
Simply..
DGhyd DGwater- DGvacuum , where
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Solvents particles
Acetic acid
Phenol
Acetone
1-propanol
1-butanol
Ethanol
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Hydration energy for solvents particles
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Error analysis for solvent particles
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Small proteins
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Hydration energy for small proteins
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Results
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Discussion
In case of solvent particles, BEM is very
accuracy. But for proteins, BEM is not good.
-Problem
Parameter (most important problem)
Solvent particles -gt MOPAC parameter (quantum
base)
Proteins -gt protonating with AMBER, calculate
with OPLS PARSE parameter may improve the
accuracy. (J. Phy. Chem. 1994, 98, 1978-1988)