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RASPA => Output files => Topic started by: Daqiang on April 07, 2018, 03:08:37 PM

Title: ENERGY DRIFT
Post by: Daqiang on April 07, 2018, 03:08:37 PM

Hi Dr Dubbeldam:
   I used the RASPA2.0.3 to simulate the isotherm of acetylene. However, when the pressure is higher than about 1500 Pa, I got a warning in the output file.
   
Simulation finished,  1 warnings
WARNING: ENERGY DRIFT (INTERNAL CONSISTENCY ERROR IN THE CODE), THE SIMULATION RESULTS ARE WRONG!!

How can I resolve the warning? Adding the NumberOfCycles?

Thanks,

Daqiang

Title: Re: ENERGY DRIFT
Post by: David Dubbeldam on April 07, 2018, 04:28:20 PM

For any error, always retry with the latest version (which is RASPA 2.0.30).

Title: Re: ENERGY DRIFT
Post by: Daqiang on April 10, 2018, 08:50:56 AM

Thank David. Using the latest version, I have resolve the issue.

Title: Re: ENERGY DRIFT
Post by: Somananda Sanyal on March 04, 2019, 01:49:48 PM

Dear Dr. Dubbeldam,

    I am getting the same error with the latest version of RASPA, i.e. 2.0.35.
How to resolve the warning and if I may know too why is it occurring?

Thanks.
Somananda

Title: Re: ENERGY DRIFT
Post by: David Dubbeldam on March 06, 2019, 02:29:19 PM

This can possibly occur when not all potentials are well-defined. An example is when the hydrogens do NOT have a Lennard-Jones potential, but the connecting atom has a VDW radius that encompasses the hydrogen (or it should). But if the VDW radius is too small, then at high density the atoms will start to overlap leading to numerical problems.