<div dir="ltr"><div>Dear all,<br><br>I generated cubic fcc(111) in the form of 3x2x2 type structure (6 layers and each layer has 12 atoms) with Iridium (lattice constant:3.839 angstroms).<br>In the generated coordinates file, crystal axes are 8.14374880, 9.40359112, 13.29868610 (generated coordinate are attached). Can i represent<br>CELL_PARAMETERS angstrom in addition to ibrav=0 in the system namelist as shown below (for whole Iridium structure).<br>8.14374880  0.00000000    0.000000000<br>0.00000000  9.40359112    0.000000000<br>0.00000000  0.00000000    13.29868610<br><br>Is the above representation correct (maintains cubic fcc), if not, please suggest me how to represent CELL_PARAMETERS for whole Iridium structure.<br>I am new user and please suggest me correct way of doing calculations.<br><br></div>Again, I want to keep manually methane molecule on the top of Iridium (on the top of z-axis, above 5 angstroms from the top atom in the z-axis), then the resultant whole structure maintain fcc cubic. Please give some suggestions. I am new to quantum espresso calculations.  <br><div><br>      72      72      72      72<br>     8.14374880     9.40359112    13.29868610     0.00000000     0.00000000     0.00000000  MD time =   0.000E+00 ps<br>Ir           6.78645733          5.48542817          6.64934305<br>Ir           5.42916587          7.83632593          6.64934305<br>Ir           5.42916587          4.70179556          4.43289536<br>Ir           6.78645733          7.05269336          4.43289536<br>Ir           5.42916587          6.26906075          2.21644768<br>Ir           6.78645733          8.61995854          2.21644768<br>Ir           4.07187440          5.48542817          6.64934305<br>Ir           2.71458293          7.83632593          6.64934305<br>Ir           2.71458293          4.70179556          4.43289536<br>Ir           4.07187440          7.05269336          4.43289536<br>Ir           2.71458293          6.26906075          2.21644768<br>Ir           4.07187440          8.61995854          2.21644768<br>Ir           1.35729146          5.48542817          6.64934305<br>Ir           0.00000000          7.83632593          6.64934305<br>Ir           0.00000000          4.70179556          4.43289536<br>Ir           1.35729146          7.05269336          4.43289536<br>Ir           0.00000000          6.26906075          2.21644768<br>Ir           1.35729146          8.61995854          2.21644768<br>Ir           6.78645733          0.78363261          6.64934305<br>Ir           5.42916587          3.13453037          6.64934305<br>Ir           5.42916587          0.00000000          4.43289536<br>Ir           6.78645733          2.35089780          4.43289536<br>Ir           5.42916587          1.56726519          2.21644768<br>Ir           6.78645733          3.91816298          2.21644768<br>Ir           4.07187440          0.78363261          6.64934305<br>Ir           2.71458293          3.13453037          6.64934305<br>Ir           2.71458293          0.00000000          4.43289536<br>Ir           4.07187440          2.35089780          4.43289536<br>Ir           2.71458293          1.56726519          2.21644768<br>Ir           4.07187440          3.91816298          2.21644768<br>Ir           1.35729146          0.78363261          6.64934305<br>Ir           0.00000000          3.13453037          6.64934305<br>Ir           0.00000000          0.00000000          4.43289536<br>Ir           1.35729146          2.35089780          4.43289536<br>Ir           0.00000000          1.56726519          2.21644768<br>Ir           1.35729146          3.91816298          2.21644768<br>Ir           6.78645733          5.48542817          0.00000000<br>Ir           5.42916587          7.83632593          0.00000000<br>Ir           5.42916587          4.70179556         -2.21644769<br>Ir           6.78645733          7.05269336         -2.21644769<br>Ir           5.42916587          6.26906075         -4.43289537<br>Ir           6.78645733          8.61995854         -4.43289537<br>Ir           4.07187440          5.48542817          0.00000000<br>Ir           2.71458293          7.83632593          0.00000000<br>Ir           2.71458293          4.70179556         -2.21644769<br>Ir           4.07187440          7.05269336         -2.21644769<br>Ir           2.71458293          6.26906075         -4.43289537<br>Ir           4.07187440          8.61995854         -4.43289537<br>Ir           1.35729146          5.48542817          0.00000000<br>Ir           0.00000000          7.83632593          0.00000000<br>Ir           0.00000000          4.70179556         -2.21644769<br>Ir           1.35729146          7.05269336         -2.21644769<br>Ir           0.00000000          6.26906075         -4.43289537<br>Ir           1.35729146          8.61995854         -4.43289537<br>Ir           6.78645733          0.78363261          0.00000000<br>Ir           5.42916587          3.13453037          0.00000000<br>Ir           5.42916587          0.00000000         -2.21644769<br>Ir           6.78645733          2.35089780         -2.21644769<br>Ir           5.42916587          1.56726519         -4.43289537<br>Ir           6.78645733          3.91816298         -4.43289537<br>Ir           4.07187440          0.78363261          0.00000000<br>Ir           2.71458293          3.13453037          0.00000000<br>Ir           2.71458293          0.00000000         -2.21644769<br>Ir           4.07187440          2.35089780         -2.21644769<br>Ir           2.71458293          1.56726519         -4.43289537<br>Ir           4.07187440          3.91816298         -4.43289537<br>Ir           1.35729146          0.78363261          0.00000000<br>Ir           0.00000000          3.13453037          0.00000000<br>Ir           0.00000000          0.00000000         -2.21644769<br>Ir           1.35729146          2.35089780         -2.21644769<br>Ir           0.00000000          1.56726519         -4.43289537<br>Ir           1.35729146          3.91816298         -4.43289537<br><br></div><div>Venkat<br></div><div>PhD research scholar<br></div><div>IIT Bombay<br></div><div>Mumbai<br></div><div><br></div></div>