linear response TDDFT calculations


Click here for full thread
Clicked A Few Times
I am using the latest NWChem 6.5 version.
I want to compute the excited state charge density and electrostatic potential of a system. For this I used the grad directive of TDDFT. But everytime error comes as 'unknown directive'. Where am I going wrong?

My input file is
START water
TITLE "tddft test"
GEOMETRY
O  0.00000000 0.00000000  0.12982363
H 0.75933475 0.00000000 -0.46621158
H -0.75933475 0.00000000 -0.46621158
END

BASIS
  • library 6-31G*
END

DFT
XC B3LYP
END

TDDFT
cis
NROOTS 20
civecs
grad
root 1
end
END
TASK tddft optimize
TASK TDDFT ENERGY


and the output error is

tddft_input: filename not found; default name will be used
------------------------------------------------------------------------
tddft_input: unknown directive 0
------------------------------------------------------------------------
There is an error in the input file
------------------------------------------------------------------------