Example #1
0
    def test_adc2_shift_invert_singlets(self):
        refdata = cache.reference_data["h2o_sto3g"]
        matrix = adcc.AdcMatrix("adc2", LazyMp(cache.refstate["h2o_sto3g"]))
        conv_tol = 1e-5
        shift = -0.5

        # Construct shift and inverted matrix:
        shinv = IterativeInverse(AdcMatrixShifted(matrix, shift),
                                 conv_tol=conv_tol / 10,
                                 Pinv=JacobiPreconditioner,
                                 callback=cg_print)

        # Solve for singlets
        guesses = adcc.guesses_singlet(matrix, n_guesses=5, block="ph")
        symm = IndexSpinSymmetrisation(matrix, enforce_spin_kind="singlet")
        res = lanczos(shinv,
                      guesses,
                      n_ep=5,
                      callback=la_print,
                      explicit_symmetrisation=symm)
        assert res.converged

        # Undo spectral transformation and compare
        eigenvalues = sorted(1 / res.eigenvalues - shift)
        ref_singlets = refdata["adc2"]["singlet"]["eigenvalues"][:5]
        assert eigenvalues == approx(ref_singlets)
Example #2
0
    def test_adc2_singlets(self):
        refdata = cache.reference_data["h2o_sto3g"]
        matrix = adcc.AdcMatrix("adc2", LazyMp(cache.refstate["h2o_sto3g"]))

        # Solve for singlets
        guesses = adcc.guesses_singlet(matrix, n_guesses=9, block="s")
        res = jacobi_davidson(matrix, guesses, n_ep=9)

        ref_singlets = refdata["adc2"]["singlet"]["eigenvalues"]
        assert res.converged
        assert res.eigenvalues == approx(ref_singlets)
Example #3
0
    def test_adc2_singlets(self):
        refdata = cache.reference_data["h2o_sto3g"]
        matrix = adcc.AdcMatrix("adc2", LazyMp(cache.refstate["h2o_sto3g"]))

        # Solve for singlets
        guesses = adcc.guesses_singlet(matrix, n_guesses=5, block="ph")
        res = lanczos(matrix, guesses, n_ep=5, which="SM")

        ref_singlets = refdata["adc2"]["singlet"]["eigenvalues"][:5]
        assert res.converged
        assert res.eigenvalues == approx(ref_singlets)
Example #4
0
    def test_diagonalise_adcmatrix(self):
        from adcc.workflow import diagonalise_adcmatrix

        refdata = cache.reference_data["h2o_sto3g"]
        matrix = adcc.AdcMatrix("adc2",
                                adcc.LazyMp(cache.refstate["h2o_sto3g"]))

        res = diagonalise_adcmatrix(matrix,
                                    n_states=3,
                                    kind="singlet",
                                    eigensolver="davidson")
        ref_singlets = refdata["adc2"]["singlet"]["eigenvalues"]
        assert res.converged
        assert res.eigenvalues == approx(ref_singlets[:3])

        guesses = adcc.guesses_singlet(matrix, n_guesses=6, block="ph")
        res = diagonalise_adcmatrix(matrix,
                                    n_states=3,
                                    kind="singlet",
                                    guesses=guesses)
        ref_singlets = refdata["adc2"]["singlet"]["eigenvalues"]
        assert res.converged
        assert res.eigenvalues == approx(ref_singlets[:3])

        with pytest.raises(InputError):  # Too low tolerance
            res = diagonalise_adcmatrix(matrix,
                                        n_states=9,
                                        kind="singlet",
                                        eigensolver="davidson",
                                        conv_tol=1e-14)

        with pytest.raises(InputError):  # Wrong solver method
            res = diagonalise_adcmatrix(matrix,
                                        n_states=9,
                                        kind="singlet",
                                        eigensolver="blubber")

        with pytest.raises(InputError):  # Too few guesses
            res = diagonalise_adcmatrix(matrix,
                                        n_states=9,
                                        kind="singlet",
                                        eigensolver="davidson",
                                        guesses=guesses)