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		                        | 10:32:26 AM PST - Thu, Feb 20th 2014  | 
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		                        Hello.  
I just wanted some clarification for the units used for the mass-weighted nuclear hessian: 
 
         ---------------------------------------------------- 
         MASS-WEIGHTED NUCLEAR HESSIAN (Hartree/Bohr/Bohr/Kamu) 
         ---------------------------------------------------- 
 
 
 
             1           2           3           4           5           6           7           8           9          10 
  ----- ----- ----- ----- ----- 
   1   4.70295D+00 
   2  -1.83038D+00 2.19102D+00 
   3   6.92036D-01-1.06888D-01 1.68451D+00 
   4  -8.03100D+00 3.66156D+00-1.17258D+00 2.98182D+01 
   5   3.82045D+00-2.96176D+00 5.34470D-01-1.50857D+01 1.06205D+01 
   6  -1.30787D+00 6.08512D-01-1.23096D+00 5.16874D+00-2.46885D+00 3.48917D+00 
   7  -8.10081D+00 3.83281D+00-1.30470D+00-4.98934D-01 7.43401D-01-2.33418D-01  
 
 
 
 
 
The output file says the units are Hartree/Bohr/Bohr/Kamu, so does this mean the hessian is divided by 1000*amu? I am trying to calculate the force constants from the mass-weighted nuclear hessian so I am wondering whether I need to multiply the values by 1000 and the atomic masses to get the force constants or whether I need to divide by 1000 and multiply by amu. 
 
Also, I know Gaussian09 provides the force constant matrix in the output file, and was wondering whether there is a keyword I can use in NWChem to also get the force constant matrix.  
 
Thank you in advance for your time and help! 
 
Sandy Fernando
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