I am using the same umbrella sampling script in the test case and I have few question regarding on that and I would like to clarify them first.
I am considering the reaction coordinate as the distance between the two atoms.
rxncor: umbrella kumb 15.0 form 1 del0 -0.4
rxncor: statistics lowdelta -0.6 hidelta -0.4 deldel 0.002 -
With regard to above command, if I am correct ,
1). del0 is the initial distance between the specified two points and is it negetive or it is just a dash?.
2). Since the potential is applied between the lowdelta and hidelta. What refers to low and hidelta?. Just in case if I need to maintain the reaction distance in between the 3.3 and 2.5 obviously the delo is 3.5 and then can't I take the lowdelta as 3.5 and also Do I need to specify the minus symbol as well? If so why is it??.