Why is my SPC water model calculating a significantly higher energy value?

  • Context: Graduate 
  • Thread starter Thread starter edie21
  • Start date Start date
  • Tags Tags
    Model Water
Click For Summary
SUMMARY

The forum discussion centers on a user encountering an anomaly in energy calculations for an SPC water model using a Monte-Carlo simulation. The user reports a calculated energy value of 50000 kJ/mol, significantly higher than the expected range of 45-48 kJ/mol found in literature. Key suggestions include verifying unit consistency and testing potential energy calculations without charges, as well as fixing the distance between hydrogen atoms in the model.

PREREQUISITES
  • Monte-Carlo simulation techniques
  • SPC water model fundamentals
  • Pascal programming language (specifically Delphi)
  • Understanding of energy units in molecular simulations
NEXT STEPS
  • Investigate unit consistency in energy calculations
  • Learn about the SPC water model and its parameters
  • Explore Monte-Carlo methods for molecular simulations
  • Examine the impact of fixed distances in molecular geometry
USEFUL FOR

Researchers and developers working on molecular simulations, particularly those focused on water models and energy calculations in computational chemistry.

edie21
Messages
1
Reaction score
0
Hello, I wrote program Monte-Carlo to calculate potential energy of SPC water molecule. But I've got a problem with energy. In all the publications reported value of the energy is 45-48 kJ/mol. However, my program calculate the value of energy significantly higher (50000 KJ/mol). I don't include relative permittivity (epsr=1). I don't know where is the mistake (my model -soft sphere sphere with three charges immersed in the sphere, or my program is wrong). I include file with program written in pascal (object Delphi)
 

Attachments

Physics news on Phys.org
Did you check your units ?
Try to calculate the pot. energy without charges and see what you get.
 
The other thing you can try is to fix the distance between both hydrogen atoms.
 

Similar threads

Graduate Ground state energy of cube-like potential wells
  • · Replies 3 ·
Replies
3
Views
2K
Graduate Higgs inflation and quadratic gravity
  • · Replies 1 ·
Replies
1
Views
4K
Undergrad Is there new LHC data on coupling constant running?
  • · Replies 1 ·
Replies
1
Views
3K
Graduate Twistors and celestial holography
  • · Replies 21 ·
Replies
21
Views
7K
April Fool's Physics Papers 2026
  • · Replies 3 ·
Replies
3
Views
1K
Fortran Why Am I Getting an 'Out of Range in G Table' Error in FORTRAN?
  • · Replies 1 ·
Replies
1
Views
3K