[CPMD-list] why CPMD tell my cell is too small?

[cdy2000 at vip.sina.com]

Hello, everyone

I have computed the gas molecule adsorb on the surface of metal oxide, and I constructed a cell of the surface, left enough space on the surface for adsorbed molecule, It is no problem when I computed the surface alone no the adsorbed molecule, but when I added the adsorbed molecule on the surface, the output file got the error, 
    CHECK IF YOUR CELL IS NOT TOO SMALL!!!
    STOPGM! STACK OF MAIN CALLS:
    STOPGM! CALL    ATOMWF

PROGRAM STOPS IN SUBROUTINE DSYGVX| FAILED TO DIAGONALIZE

but I have not changed any data about the cell parameter only added some adsorbed molecule coordinations in the part of &ATOMS &END, I want to know why and how to solve it?

Thanks for any help

Sincerely Cao Dayong
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