def test_spin_align_so(self, setup):
bond = 1.42
sq3h = 3.**.5 * 0.5
sc = SuperCell(np.array([[1.5, sq3h, 0.],
[1.5, -sq3h, 0.],
[0., 0., 10.]], np.float64) * bond, nsc=[3, 3, 1])
orb = AtomicOrbital('px', R=bond * 1.001)
C = Atom(6, orb)
g = Geometry(np.array([[0., 0., 0.],
[1., 0., 0.]], np.float64) * bond,
atoms=C, sc=sc)
D = DensityMatrix(g, spin=Spin('SO'))
D.construct([[0.1, bond + 0.01], [(1., 0.5, 0.01, 0.01, 0.01, 0.01, 0.2, 0.2), (0.1, 0.2, 0.1, 0.1, 0., 0.1, 0.2, 0.3)]])
D_mull = D.mulliken()
v = np.array([1, 2, 3])
d = D.spin_align(v)
d_mull = d.mulliken()
assert not np.allclose(D_mull, d_mull)
assert np.allclose(D_mull[:, 0], d_mull[:, 0])
def test_spin_align_pol(self, setup):
bond = 1.42
sq3h = 3.**.5 * 0.5
sc = SuperCell(np.array(
[[1.5, sq3h, 0.], [1.5, -sq3h, 0.], [0., 0., 10.]], np.float64) *
bond,
nsc=[3, 3, 1])
orb = AtomicOrbital('px', R=bond * 1.001)
C = Atom(6, orb)
g = Geometry(np.array([[0., 0., 0.], [1., 0., 0.]], np.float64) * bond,
atom=C,
sc=sc)
D = DensityMatrix(g, spin=Spin('p'))
D.construct([[0.1, bond + 0.01], [(1., 0.5), (0.1, 0.2)]])
D_mull = D.mulliken()
v = np.array([1, 2, 3])
d = D.spin_align(v)
d_mull = d.mulliken()
assert D_mull.shape == (len(D), 2)
assert d_mull.shape == (len(D), 4)
assert not np.allclose(-np.diff(D_mull, axis=1), d_mull[:, 3])
assert np.allclose(D_mull.sum(1), d_mull[:, 0])