Using a text editor, open the “name-of-file.dat” and remove the “Tv” and the entire “mers=(x,1,1)” command line (near the bottom and top of the line) and change the ghost atom (“xx”) back into a hydrogen, H, atom (or what ever atom one used) to be viewed with Hyperchem Pro 5.1. Simply rename this modified file and save the file out as a *.zmt file and check the structure by opening it back into the Hyperchem 5.1 Pro (see figure 2.2 and Appendix F). As shown in figure 2.2, the program was able to generate the repeating structure with all its atoms using the original unit cell after running the job on makpol.exe.
57 mers(2,1,1) unit cell from C 60 mers(3,1,1) unit cell from C 60 mers(4,1,1) unit cell from C 60 Figure 2.2: Checking the “make file” after running in makpol.exe to generate the polymer of unit cells. The unit cell was taken from C 60 and (2,1,1), (3,1,1), and (4,1,1) were the repeating unit used to generate a SWNT, C 120 , C 180 , and C 240 , structures consisting of 120, 180, and 240 carbon atoms.
58 2.5.1 The types of jobs done using MOPAC 2000 on the [5,5] armchair SWNT Once the files have been checked, the following calculations are performed using the MOPAC 2000 utility package: 1) a single-point (SP) with no PBC enforced, 2) a SP calculation with PBC enforced, and 3) optimize the molecule with PBC enforced. All jobs determined the heat of formation for each molecule. Of the three jobs done, the most important is 3) imposing PBC while optimizing the molecule. These optimized PBC structures would then be used to determine: 1) the repeating unit cell, 2) which C n [5,5] armchair SWNT belongs to the repeating unit, and 3) how many diameter(s) and carbon-carbon bond distance(s) are there for an infinite length of the [5,5] armchair SWNT at bulk.
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