Another Raman question - WARNING: CPKS procedure is NOT converged


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Hello,
So I am doing some raman calculations for a polyetylene chain with up to 26 atoms. During the "Solving response equations for perturbing field" section I get the follwoign error:

-----------------------------------------------
Solving response equations for perturbing field
-----------------------------------------------

number of frequencies:     1
frequency in a.u.: 0.8855900E-01
Perturbing field: electric
Using Dipole Length Gauge

Applying DAMPING constant of 0.007000 a.u.

(lstatic,omega,ncomp)=(F, 0.08855900, 2)
Setting up CPKS
with frequency omega = 0.08855900 a.u.
and a damping of 0.00700000 a.u.


NWChem Dynamic CPHF Module
--------------------------


scftype = RHF
nclosed = 85
nopen = 0
variables = 103360
num. vecs = 3
tolerance = 1.0D-04
max. iter = 50

SCF residual:   3.650751700989796E-004


Iterative solution of linear equations
 No. of variables    51680
No. of equations 3
Maximum subspace 33
Convergence 1.0D-04
Start time 3518.3


  iter   nsub   residual    time 
---- ------ -------- ---------
dft_CPHF2_read: failed to open./c28.aoresp_fiao_f1
File ./c28.aoresp_fiao_f1 does not exist, proceed to generate (z1,Az1)
....
WARNING: CPKS procedure is NOT converged
I will proceed, but check your results carefully!!!


this is my input file:

title "TDDFT monomer B3LYP/6-31G*"

geometry units angstroms
load monomer.xyz
end

basis spherical
H library 6-31G*
C library 6-31G*
end

dft
xc b3lyp  
direct
tolerances tight
iterations 1000
end

hessian
thresh 1d-8
profile
end

property
response  1 8.8559E-2
damping 0.007
end

raman
 normal
end

driver
maxiter 30
xyz opt
end

task dft optimize
task dft raman numerical

freq
reuse
end

task dft freq


I was wondering if anyone would know how to solve this problem?
The thing is that when I see the resulting raman spectra (*.normal) the peaks seem very noisy and they dont make much sense. for example, I see multiple instances of the C-C vibrational mode at different frequencies and things of that sort.


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