[gmx-users] error found when doing tpi calculations

[Yakun]

Dear all,
I am using test particle insertion (tpi) method to calculate the henry constant for CO2 dissovling in spce water. I have read the manual and also a webpage (https://www.svedruziclab.com/tutorials/gromacs/6-tpi/). However, the last step 'gmx mdrun -deffnm tpi -rerun npt' gave me the following error message
'Fatal error:
Can not do TPI for multi-atom molecule with a twin-range cut-off
For more information and tips for troubleshooting, please check the GROMACS
website at http://www.gromacs.org/Documentation/Errors'
I guessed that I have make rvdw and rcoulomb different. But setting different data for rvdw and rcoulomb did not work. 
Anyone know what I did wrong. Any advice? Thanks in advance

Yakun Chen