Coverage for gpaw/test/fdtd/test_ed.py: 100%

1import pytest 

2from gpaw import GPAW 

3from gpaw.tddft import TDDFT, DipoleMomentWriter 

4 

5 

6@pytest.mark.old_gpaw_only 

7def test_fdtd_ed(in_tmp_dir, gpw_files): 

8 # Accuracy 

9 energy_eps = 0.0005 

10 

11 # load gpw file 

12 gs_calc = GPAW(gpw_files['na2_isolated']) 

13 energy = gs_calc.get_potential_energy() 

14 

15 # Test ground state 

16 assert energy == pytest.approx( 

17 -0.631881, abs=energy_eps * gs_calc.get_number_of_electrons()) 

18 

19 # Test floating point arithmetic errors 

20 assert gs_calc.hamiltonian.poisson.shift_indices_1 == pytest.approx( 

21 [4, 4, 10], abs=0) 

22 assert gs_calc.hamiltonian.poisson.shift_indices_2 == pytest.approx( 

23 [8, 8, 16], abs=0) 

24 

25 # Initialize TDDFT and FDTD 

26 kick = [0.0, 0.0, 1.0e-3] 

27 time_step = 10.0 

28 max_time = 100 # 0.1 fs 

29 

30 td_calc = TDDFT(gpw_files['na2_isolated']) 

31 DipoleMomentWriter(td_calc, 'dm.dat') 

32 td_calc.absorption_kick(kick_strength=kick) 

33 

34 # Propagate TDDFT and FDTD 

35 td_calc.propagate(time_step, max_time / time_step / 2) 

36 td_calc.write('td.gpw', 'all') 

37 

38 td_calc2 = TDDFT('td.gpw') 

39 DipoleMomentWriter(td_calc2, 'dm.dat') 

40 td_calc2.propagate(time_step, max_time / time_step / 2) 

41 

42 # Test 

43 ref_cl_dipole_moment = [5.25374117e-14, 5.75811267e-14, 3.08349334e-02] 

44 ref_qm_dipole_moment = [1.78620337e-11, -1.57782578e-11, 5.21368300e-01] 

45 

46 tol = 1e-4 

47 assert td_calc2.hamiltonian.poisson.get_classical_dipole_moment() == ( 

48 pytest.approx(ref_cl_dipole_moment, abs=tol)) 

49 assert td_calc2.hamiltonian.poisson.get_quantum_dipole_moment() == ( 

50 pytest.approx(ref_qm_dipole_moment, abs=tol))