root / ase / test / emt1.py @ 4
Historique | Voir | Annoter | Télécharger (632 octet)
| 1 | 1 | tkerber | from ase import Atoms |
|---|---|---|---|
| 2 | 1 | tkerber | from ase.calculators.emt import EMT |
| 3 | 1 | tkerber | from ase.constraints import FixBondLength |
| 4 | 1 | tkerber | from ase.io import PickleTrajectory |
| 5 | 1 | tkerber | from ase.optimize import BFGS |
| 6 | 1 | tkerber | |
| 7 | 1 | tkerber | a = 3.6
|
| 8 | 1 | tkerber | b = a / 2
|
| 9 | 1 | tkerber | cu = Atoms('Cu2Ag',
|
| 10 | 1 | tkerber | positions=[(0, 0, 0), |
| 11 | 1 | tkerber | (b, b, 0),
|
| 12 | 1 | tkerber | (a, a, b)], |
| 13 | 1 | tkerber | calculator=EMT()) |
| 14 | 1 | tkerber | e0 = cu.get_potential_energy() |
| 15 | 1 | tkerber | print e0
|
| 16 | 1 | tkerber | |
| 17 | 1 | tkerber | d0 = cu.get_distance(0, 1) |
| 18 | 1 | tkerber | cu.set_constraint(FixBondLength(0, 1)) |
| 19 | 1 | tkerber | t = PickleTrajectory('cu2ag.traj', 'w', cu) |
| 20 | 1 | tkerber | qn = BFGS(cu) |
| 21 | 1 | tkerber | qn.attach(t.write) |
| 22 | 1 | tkerber | def f(): print cu.get_distance(0,1) |
| 23 | 1 | tkerber | qn.attach(f) |
| 24 | 1 | tkerber | qn.run(fmax=0.01)
|
| 25 | 1 | tkerber | assert abs(cu.get_distance(0, 1) - d0) < 1e-14 |