[CPMD-list] EWALD SUM not equal in real and Q-space

[Shiwu Gao]

Hi,

I got a trouble in running CPMD with the Vanderbildt uspp, 
which I generated myself. The program stops and complains that
the Ewald sum does not equal in real and Fourier Q-space, 

Typical error message looks like this 

  ****************************************************************

 CPU TIME FOR WAVEFUNCTION INITIALIZATION:           8.73 SECONDS
 ***    RWFOPT| THE NEW SIZE OF THE PROGRAM IS   13844 kBYTES ***
 EWALD SUM IN REAL SPACE OVER  5* 5* 5 CELLS
IN FOURIER SPACE:                               360.000005713858
IN REAL SPACE:                                  359.999999999984

 *****************************************************************

Note the charge should be 360 in this case. Tested many uspp's including
the potential included in the latest uspp package. All have the same 
problem. Note that the sum in real space is usually OK with an error 
less than 10^-10, while the error in Q-space is large, 10^-5--10^-6. 

Has anybody met this problem with uspp? What is the way out of it? 

Thanks in advance,

Shiwu Gao