Example of data for polytetrahydrofuran

The following example illustrates the data file for a four hour polytetrahydrofuran calculation. As you can see the layout of the data is almost the same as that for a molecule, the main difference is in the presence of the translation vector atom ``Tv''.

         
  Line 1 :T=4H
  Line 2 :      POLY-TETRAHYDROFURAN (C4 H8 O)2
  Line 3 : 
  Line 4a:   C    0.000000  0    0.000000  0    0.000000  0   0  0  0
  Line 4b:   C    1.551261  1    0.000000  0    0.000000  0   1  0  0
  Line 4c:   O    1.401861  1  108.919034  1    0.000000  0   2  1  0
  Line 4d:   C    1.401958  1  119.302489  1 -179.392581  1   3  2  1
  Line 4e:   C    1.551074  1  108.956238  1  179.014664  1   4  3  2
  Line 4f:   C    1.541928  1  113.074843  1  179.724877  1   5  4  3
  Line 4g:   C    1.551502  1  113.039652  1  179.525806  1   6  5  4
  Line 4h:   O    1.402677  1  108.663575  1  179.855864  1   7  6  5
  Line 4i:   C    1.402671  1  119.250433  1 -179.637345  1   8  7  6
  Line 4j:   C    1.552020  1  108.665746  1 -179.161900  1   9  8  7
  Line 4k:  XX    1.552507  1  112.659354  1 -178.914985  1  10  9  8
  Line 4l:  XX    1.547723  1  113.375266  1 -179.924995  1  11 10  9
  Line 4m:   H    1.114250  1   89.824605  1  126.911018  1   1  3  2
  Line 4n:   H    1.114708  1   89.909148  1 -126.650667  1   1  3  2
  Line 4o:   H    1.123297  1   93.602831  1  127.182594  1   2  4  3
  Line 4p:   H    1.123640  1   93.853406  1 -126.320187  1   2  4  3
  Line 4q:   H    1.123549  1   90.682924  1  126.763659  1   4  6  5
  Line 4r:   H    1.123417  1   90.679889  1 -127.033695  1   4  6  5
  Line 4s:   H    1.114352  1   90.239157  1  126.447043  1   5  7  6
  Line 4t:   H    1.114462  1   89.842852  1 -127.140168  1   5  7  6
  Line 4u:   H    1.114340  1   89.831790  1  126.653999  1   6  8  7
  Line 4v:   H    1.114433  1   89.753913  1 -126.926618  1   6  8  7
  Line 4w:   H    1.123126  1   93.644744  1  127.030541  1   7  9  8
  Line 4x:   H    1.123225  1   93.880969  1 -126.380511  1   7  9  8
  Line 4y:   H    1.123328  1   90.261019  1  127.815464  1   9 11 10
  Line 4z:   H    1.123227  1   91.051403  1 -125.914234  1   9 11 10
  Line 4A:   H    1.113970  1   90.374545  1  126.799259  1  10 12 11
  Line 4B:   H    1.114347  1   90.255788  1 -126.709810  1  10 12 11
  Line 4C:  Tv   12.299490  1    0.000000  0    0.000000  0   1 11 10
  Line 5 :   0    0.000000  0    0.000000  0    0.000000  0   0  0  0

Polytetrahydrofuran has a repeat unit of $\rm\everymath={\rm }(C_4H_8O)_2$; i.e., twice the monomer unit. This is necessary in order to allow the lattice to repeat after a translation through $12.3$ Å. See the section on Solid State Capability for further details.

Note the two dummy atoms on lines 4k and 4l. These are useful, but not essential, for defining the geometry. The atoms on lines 4y to 4B use these dummy atoms, as does the translation vector on line 4C. The translation vector has only the length marked for optimization. The reason for this is also explained in the Background chapter.