[CPMD-list] geometry optimization of a carbon nanotube

Hiroshi Amawashi k3135005 at guedu.cc.gifu-u.ac.jp
Sun Dec 4 02:28:50 CET 2005


Dear CPMD community,

I'm a beginner of CPMD and trying to do a geometry optimization of 
an armchair-type carbon nanotube with chiral vector of (5,5).

But the results were bizarre: 20-atom armchair ring in the unit cell
had broken into two parts. When I set TESR = 8, the bond angles of
armchir were `optimized' to around 100 degrees rather than the normal angle
of 120 degrees. Obviously, these results are all wrong.  

Any useful suggestions would be greatly appreciated. I've included the 
input file that I'm using below, in case I'm making a stupid mistake......
Best wishes,

Hiroshi Amawashi

------------------INPUT FILE


&CPMD                                                                    
OPTIMIZE GEOMETRY XYZ                                                    
ODIIS                                                                    
4                                                                        
TSDC                                                                     
SPLINE RANGE                                                             
5.0                                                                      
BFGS                                                                     
STRUCTURE BONDS ANGLES                                                   
MIRROR                                                                   
HESSIAN UNIT                                                             
&END                                                                     
                                                                          
&SYSTEM                                                                  
SYMMETRY                                                                 
6                                                                        
ANGSTROM                                                                
CELL                                                                     
10.0 1.0 0.2494153 0.0 0.0 0.0                                           
CUTOFF                                                                  
80.                                                                      
TESR                                                                     
8                                                                        
POINT GROUP                                                              
AUTO                                                                     
&END                                                                     
                                                                          
&ATOMS                                                                   
Carbon                                                                   
C_MT_GIA_BLYP    KLEIMANN-BYLANDER                                       
LMAX=P LOC=P                                                             
20                                                                       
     3.4377467708   0.0000000000  0.0000000000                            
     3.1405379470   1.3982575813  0.0000000000                            
     2.7811955599   2.0206568530  1.2470765814                            
     1.7188733854   2.9771760353  1.2470765814                            
     1.0623221745   3.2694914677  -0.0000000000                           
     -0.3593423871  3.4189144343  -0.0000000000                           
     -1.0623221745  3.2694914677  1.2470765814                            
     -2.3003015812  2.5547437240  1.2470765814                            
     -2.7811955599  2.0206568530  -0.0000000000                           
     -3.3626237558  0.7147477437  -0.0000000000                           
     -3.4377467708  0.0000000000  1.2470765814                            
     -3.1405379470  -1.3982575813  1.2470765814                            
     -2.7811955599  -2.0206568530  -0.0000000000                           
     -1.7188733854  -2.9771760353  -0.0000000000                           
     -1.0623221745  -3.2694914677  1.2470765814                            
     0.3593423871   -3.4189144343  1.2470765814                            
     1.0623221745   -3.2694914677  -0.0000000000                           
     2.3003015812   -2.5547437240  -0.0000000000                           
     2.7811955599   -2.0206568530  1.2470765814                            
     3.3626237558   -0.7147477437  1.2470765814                            
&END                                                                     
                                                                         
&DFT                                                                     
FUNCTIONAL BLYP                                                          
&END                                                                     
---------------------End of INPUT FILE


----------------------------------------------------------------
Hiroshi Amawashi
University of Gifu
1-1 , yanagido , Gifu City, Gifu, Japan
E-mail: k3135005 at guedu.cc.gifu-u.ac.jp
----------------------------------------------------------------

----
Hiroshi Amawashi  k3135005 at guedu.cc.gifu-u.ac.jp



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