2.4. QUICK START OF BALSAC

next, previous Section / Table of Contents / Index To give the impatient user a flavor of the BALSAC system two sample sessions will be given below by listing only the commands to be entered and the results of this input without a detailed explanation. For a full tutorial Sec. 3 may be consulted. It is assumed that BALSAC has been correctly installed in a DOS/VGA or Unix/X.11 environment and the display settings (on Unix systems) are correct. In the following, input to BALSAC is entered from the keyboard where "[x]" denotes "press key x on the keyboard". Further, "numbers/text" means "type the text/values inside the double quotes, " ", followed by the enter key". (A) Build and view a lattice section showing the (001) face of the cubic Zincblende lattice. command action ----------------------------------------------------------------------------- "balsac -l" starts a BALSAC/LATTICE session. [i] starts an interactive session from scratch. [h] selects a Zincblende lattice. "1." selects a lattice constant a = 1. "0,0,1" selects Miller indices (001) for surface orientation. "3,4,7,1" selects a section of 3 x 4 x 7 atoms, finishes with 1st termination plane. [,] skips view options, using view defaults. [,] skips graphics options, using the default graphic values, and moves to main option menu of the BALSAC/LATTICE session. [x] displays the lattice section: see layers of Zn atoms (small balls) and S atoms (large balls). The layers are painted differently. [,] returns to main option menu. [s], [b], "4,5,7" increases the crystal section block. [,] returns to main option menu. [v], [t], "60,10" changes view angle theta to 60 degrees (10 degrees increment, see below). [p], "65,10" changes viewing angle phi to 65 degrees (10 degrees increment, see below). [q], "3,1" turns on central perspective. [,] returns to main option menu. [g], [d], [d] displays atoms as dither-shaded balls. [l], [p] colors atoms according to their nuclear charge. [x] views the modified lattice section: pretty 3-dimensional picture of the lattice section. [up arrow] or [8] rotates the lattice section (theta increased by 10 degrees) and plots again. [left arrow] or [4] rotates the lattice section (phi decreased by 10 degrees) and plots again. [m] shrinks picture of lattice section. [M] blows up picture of lattice section to previous size. [,] returns to main option menu. [o], [q] saves lattice structure on file 'balsac.lat'. [,], [q] exits from BALSAC. "balsac -lr" starts a BALSAC/LATTICE session with the previously saved lattice structure as input. ----------------------------------------------------------------------------- (B) Build and view a benzene (C6H6) molecule. command action ----------------------------------------------------------------------------- "balsac -c" starts a BALSAC/CLUSTER session. [i] starts an interactive session from scratch. "C6H6 molecule" provides molecule title. "2" starts with two atoms (C, H) only. "1.4,0,0,0,6" defines one C atom (x,y,z, dummy radius, atomic number). "2.5,0,0,0,1" defines one H atom (x,y,z, dummy radius, atomic number). [s], [c] imposes symmetry (rotation axis). "0,0,0,0" defines symmetry origin (0, x,y,z). "0,0,1,6" defines direction of rotation axis (x,y,z) and order (6). ( [c] ) returns to structure menu (BALSAC DOS version only). [,] moves to view menu. [,] skips view options, using view defaults. [,] skips graphics options, using the default graphic values, and moves to main option menu of the BALSAC/CLUSTER session. [r], [r], [c] renormalizes atom radii. [x] displays the molecule: planar view with C atoms (large balls) and H atoms (small balls). Elements are painted differently. [,] returns to main option menu. [r], [a], [r], ".8" shrinks all atom radii to 80%. [,] returns to main option menu. [g], [c] defines bonds between atoms. [n], "2" defines two bond constraints. "6,6,1.3,1.5" connects carbons (atomic number = 6) within a distance range (1.3, 1.5). "6,1,1.0,1.2" connects carbons (atomic number = 6) with hydrogens (atomic number = 1) within a distance range (1.0, 1.2). [r], "0.15,0.1" defines bond thicknesses (stick radii). [x] displays the molecule: planar view of C6H6 with bonds. [o], [v], [q], "3,1" turns on central perspective. [x] displays the molecule: still planar view. [up arrow] or [8] rotates the molecule (theta increased by 10 degrees) and plots again. Repeat with [up arrow]. [left arrow] or [4] rotates the molecule (phi decreased by 10 degrees) and plots again. Repeat with [left arrow]. [,] returns to main option menu. [o], [q] saves molecule structure on file 'balsac.plt'. [,], [q] exits from BALSAC. "balsac -cr" starts a BALSAC/CLUSTER session with the previously saved molecule structure as input. ----------------------------------------------------------------------------- next, previous Section / Table of Contents / Index