How to obtain rpath

Questions
#1

We have successfully upgraded to Q-Chem 6.0.2, but it does not seem to have solved our current problems. How do we get the mass-weighted coordinate on the one hand, or do we know how to calculate this coordinate from mass and coordinates? We have not found any papers on this and need your help urgently. Secondly, we find that the current output file contains only three step structures, are these three structures on the reaction path or are they the reactant and product structures inferred from the transition state? If it is the latter, that would be terrible as this is not the reactant and product structures we have entered. Our current input file is as follows:
$rem
JOBTYPE ts
BASIS aug-cc-pVTZ
METHOD pbe0
DFT_D = D3_BJ
MAX_SCF_CYCLES 25000000
GEOM_OPT_DMAX 50
GEOM_OPT_MAX_CYCLES 10000000000
GEOM_OPT_TOL_DISPLACEMENT=60
GEOM_OPT_TOL_GRADIENT 20
GEOM_OPT_TOL_ENERGY 20
SYMMETRY false
SYM_IGNORE true
$end

@@@

$molecule
read
$end

$rem
JOBTYPE freq
METHOD pbe0
DFT_D = D3_BJ
BASIS aug-cc-pVTZ
SCF_GUESS read
$end

@@@

$molecule
read
$end

$rem
JOBTYPE rpath
BASIS aug-cc-pVTZ
METHOD pbe0
DFT_D = D3_BJ
SCF_GUESS read
RPATH_MAX_CYCLES 250000000
$end

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#2

So to use mass weighted coordinates during the rpath job you need to add in the variable rpath_coords = 0 by default rpath does Cartesian coordinates, therefore your job is in Cartesian coordinates. In addition you can use rpath_direction, see Manual Sec. 9.8, to have the calculation descend in the positive or negative direction, this choice can’t be made before the calculation. So this could explain the different path observed.

#3

Actually I think it computes the path in both directions, regardless of RPATH_DIRECTION. (Noticed this when doing cleanup of the output for v. 6.0.2.) Not sure what RPATH_DIRECTION does anymore.

#4

Thank you very much. I will adjust the commmand according to your suggestions.

#5

Thank you very much. I will think this question according to your suggestions.