From NWChem
			Viewed 335 times, With a total of 0 Posts
												
			
                  
        
            
                | 
                    
                 | 
            
            
                
                    
                        
                            | 
                 Clicked A Few Times 
                
                                Threads 3 
                                Posts 5                              
                             | 
                         
                     
                 | 
            		
		                
		                    
		                        | 12:05:46 PM PDT - Tue, May 10th 2011  | 
		                             | 
		                     
		                    
		                        Hi, 
 
I tried unsuccesfully to run a DFT QMD (quantum molecular dynamics) job of CO2 using the following input. The job ran perfectly in serial mode, but when I tried to run it in parallel the molecule exploded after a few hundred cycles. The molecule just starts to move weird and then explodes and the program returns an error due to lack of convergence of the electronic structure.  
I tried OpenMPI versions 1.4.3 and 1.4.2 and got the same results. 
I ran this job on my Athlon II X2 laptop, on an Intel Core i7 and a Core 2 Quad with the same results. 
The comand for running was 
 
mpirun -np 4 nwchem input.nw 
It's certainly not the timestep, as I checked it with a very small dt. 
Any ideas about why this happens? 
 
Thank you very much 
 
Diego 
 
_______________________________________________________ 
Title "Dinamica moleccular DFT de CO2 en vacio" 
 
permanent_dir ./co2 
scratch_dir ./scratch 
 
Start  CO2 
 
echo 
 
charge 0 
 
geometry noautosym noautoz units angstrom 
C     0.00000     0.00000     0.00000 
O     1.50000     0.00000     0.00000 
O    -1.50000     0.00000     0.00000 
 
end 
 
ecce_print ecce.out 
 
basis "ao basis" cartesian print 
 O library "3-21G*" 
 C library "3-21G*" 
 
end 
 
dft 
 mult 1 
 XC b3lyp 
 mulliken 
 print low 
 
end 
 
md 
 system CO2 
 cutoff 5.0 
 noshake solute 
 equil 1000 data 1000 step 0.002 
 isotherm 1.0 300.0 anneal 0.0 1.0 
 record rest 1000 scoor 1 prop 1 svelo 1 
 print step 1 stat 1000 energies 1 
 update motion 1000 
 
end 
 
task dft dynamics 
__________________________________________________________
 | 
		                     
		                    
	| 
		Edited On 12:57:16 PM PDT - Tue, May 10th 2011 by Diegoarmino
	 | 
 
		                 
		             | 
        
 
         | 
        
      
        	
            
                AWC's:
                 2.5.10 MediaWiki - Stand Alone Forum Extension
Forum theme style by: AWC