def testDerivBF_pxy(self):
"""
Test Derivative of the px-type basis functions in y-direction
"""
# construct integrator object
integrator = PyQInt()
# build gtos
nucleus = [-0.5, 0.0, 0.0]
gto1 = gto(0.154329, [-0.50, 0.0, 0.0], 3.425251, 1, 0, 0)
gto2 = gto(0.154329, [0.50, 0.0, 0.0], 3.425251, 1, 0, 0)
# derivative towards bf coordinates
t1 = integrator.nuclear_gto_deriv_bf(gto1, gto1, nucleus, 1)
# test the first derivative of the second hydrogen atom in the
# Cartesian direction
t2 = integrator.nuclear_gto_deriv_bf(gto2, gto2, nucleus, 1)
# also calculate this integral using finite difference
fx_fd_01 = calculate_fy_bf_finite_difference(gto1, nucleus)
fx_fd_02 = calculate_fy_bf_finite_difference(gto2, nucleus)
# testing
np.testing.assert_almost_equal(-2 * t1, fx_fd_01, 4)
np.testing.assert_almost_equal(-2 * t2, fx_fd_02, 4)
def testDerivOpt_d1(self):
"""
Test Derivative of the nuclear attraction operator in x-direction
for d-type orbitals
"""
# construct integrator object
integrator = PyQInt()
# build gtos
nucleus = np.array([-0.5, 0.0, 0.0])
gto1 = gto(0.154329, nucleus, 3.425251, 2, 0, 0)
gto2 = gto(0.154329, -nucleus, 3.425251, 2, 0, 0)
t1a = integrator.nuclear_gto_deriv_op(gto1, gto1, nucleus, 0)
t1b = integrator.nuclear_gto_deriv_bf(gto1, gto1, nucleus, 0)
t2a = integrator.nuclear_gto_deriv_op(gto2, gto2, nucleus, 0)
t2b = integrator.nuclear_gto_deriv_bf(gto2, gto2, nucleus, 0)
# also calculate this integral using finite difference
fd_01 = calculate_fx_op_finite_difference(gto1, nucleus)
fd_02a = calculate_fx_op_finite_difference(gto2, nucleus)
fd_02b = calculate_fx_bf_finite_difference(gto2, nucleus)
# testing
np.testing.assert_almost_equal(t1a, 0.0, 4)
np.testing.assert_almost_equal(t1b, 0.0, 4)
np.testing.assert_almost_equal(-2.0 * t2b, fd_02b, 4)
np.testing.assert_almost_equal(t2a, fd_02a, 4)
