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101 lines
No EOL
4.5 KiB
HTML
101 lines
No EOL
4.5 KiB
HTML
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<meta http-equiv="content-type" content="text/html;charset=iso-8859-1">
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<meta name="generator" content="Adobe GoLive 6">
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<title>Total energy of S2 dimer using local basis DFT method</title>
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<body bgcolor="#ffffff">
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<h1>Example I: Total energy of S2 dimer using local basis DFT method.</h1>
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<p>
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</p>
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<p>
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</p>
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<table border="0" cellspacing="10" cellpadding="2">
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<tr>
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<td valign="top" bgcolor="#ffccff"><i><b>INPUT FILE</b></i></td>
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<td valign="top" width="30"></td>
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<td align="left" valign="top" bgcolor="#ffffcc" width="300"><i><b>COMMENTS</b></i></td>
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</tr>
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<tr>
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<td valign="top"></td>
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<td valign="top" width="30"></td>
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<td align="left" valign="top" width="300"></td>
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</tr>
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<tr>
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<td valign="top" bgcolor="#ffccff"><font size="+1"><b>echo</b></font></td>
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<td valign="top" width="30"></td>
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<td align="left" valign="top" bgcolor="#ffffcc" width="300"><b>The first directive “echo” is optional but highly recommended. Its purpose is to write out the contents of your input file into the output file.<br>
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</b>
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<p></p>
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</td>
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</tr>
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<tr>
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<td valign="top" bgcolor="#ffccff"><font size="+1"><b>scratch_dir</b></font> <font size="+1">./scratch</font><br>
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</td>
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<td valign="top" width="30"></td>
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<td align="left" valign="top" bgcolor="#ffffcc" width="300"><b>The location scratch directory. The scratch directory contains temporary files that may be discarded after the calculation is complete.</b></td>
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</tr>
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<tr>
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<td valign="top" bgcolor="#ffccff"><font size="+1"><b>permanent_dir</b></font> <font size="+1">./perm</font><br>
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</td>
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<td valign="top" width="30"></td>
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<td align="left" valign="top" bgcolor="#ffffcc" width="300"><b>The location of permanent directory The permanent directory contains essential files which will be required should you wish to restart your calculation.</b></td>
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</tr>
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<tr>
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<td bgcolor="#ffccff"><font size="+1"><b>title</b> "S2 local basis DFT"</font></td>
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<td width="30"></td>
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<td bgcolor="#ffffcc" width="300"><b>The “title” directive is also optional. You might want to put a short sentence identifying the nature of your calculation </b></td>
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</tr>
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<tr>
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<td bgcolor="#ffccff"><font size="+1"><b>start</b> s2</font></td>
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<td width="30"></td>
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<td bgcolor="#ffffcc" width="300"><b>The "start" directive signifies that this is a new calculation. The string ( "s2" in this case ) sets up a prefix for permanent files (e.g. database file ) that will be associated with this calculation. You will need those files if you want to restart your calculation.</b></td>
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</tr>
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<tr>
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<td bgcolor="#ffccff">
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<p><font size="+1"><b>geometry</b><br>
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</font><font size="+1"> S 0.0 0.0 0.0<br>
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</font><font size="+1">S 0.0 0.0 1.95<br>
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</font><font size="+1"><b>end</b><br>
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</font></p>
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</td>
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<td width="30"></td>
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<td bgcolor="#ffffcc" width="300"><b>The geometry block specifies the name of the elements that comprise your system as well as their coordinates in the following format:<br>
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</b>
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<p><b>Name1 x1 y1 z1<br>
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Name2 x2 y2 z2<br>
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</b></p>
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<p><b>……<br>
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</b></p>
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<p><b>Unless indicated otherwise, the default units are angstroms, and the system will be centered around the origin.<br>
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</b></p>
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<p></p>
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</td>
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</tr>
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<tr>
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<td bgcolor="#ffccff">
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<p><font size="+1"><b>basis "ao basis"</b><br>
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</font></p>
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<p><font size="+1">* library "6-31++G**"<br>
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</font></p>
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<p><font size="+1"><b>end</b><br>
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</font></p>
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</td>
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<td width="30"></td>
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<td bgcolor="#ffffcc" width="300"><b>Basis block sets up local basis assignments for the elements in the system. This can be done on element-by-element basis or all at once using "star" notation. Here we are using 6-31++G** basis set</b></td>
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</tr>
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<tr>
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<td bgcolor="#ffccff"><font size="+1"><b>task dft energy</b></font></td>
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<td width="30"></td>
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<td bgcolor="#ffffcc" width="300"><b>Task directive requests the actual calculation. In this case we are using local basis DFT method (keyword dft) and requesting total energy calculation ( keyword energy) </b></td>
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</tr>
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</table>
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<p>
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</p>
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</body>
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</html> |