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Added descriptions of anharmonic free energy in documentation
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ttadano committed Mar 26, 2019
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2 changes: 1 addition & 1 deletion docs/source/conf.py
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Expand Up @@ -107,7 +107,7 @@

# The theme to use for HTML and HTML Help pages. See the documentation for
# a list of builtin themes.
html_theme = 'default'
html_theme = 'sphinx_rtd_theme'

# Theme options are theme-specific and customize the look and feel of a theme
# further. For a list of options available for each theme, see the
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15 changes: 15 additions & 0 deletions docs/source/formalism/formalism_anphon.rst
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Expand Up @@ -105,6 +105,19 @@ given as follows:
Here, :math:`k` is the Boltzmann constant. These quantities will be saved in the ``PREFIX``.thermo file.

When the self-consistent phonon mode (``MODE = SCPH``) is selected, the anharmonic free-energy
defined by the following equation will be calculated and saved in the ``PREFIX``.scph_thermo file:

.. math::
:nowrap:
\begin{align*}
F^{\mathrm{SCP}} &= \frac{1}{N_{q}}\sum_{\boldsymbol{q},j}\left[ \frac{\hbar\Omega_{\boldsymbol{q}j}}{2} + kT\log{\left( 1 - e^{-\hbar\Omega_{\boldsymbol{q}j}/kT}\right)} \right] \\
& - \frac{1}{N_{q}}\sum_{\boldsymbol{q},j}\left[ \Omega_{\boldsymbol{q}j}^{2} - (C_{\boldsymbol{q}}^{\dagger}\Lambda_{\boldsymbol{q}}^{(\mathrm{HA})}C_{\boldsymbol{q}})_{jj} \right]
\times \frac{\hbar [1 + 2n_{\boldsymbol{q}j} ]}{2\Omega_{\boldsymbol{q}j}}.
\end{align*}
Details of the derivation of the above expression can be found in Ref. [7]_.


Mean square displacement
Expand Down Expand Up @@ -445,3 +458,5 @@ When ``SELF_OFFDIAG = 1``, the off-diagonal elements are also calculated, and th
.. [5] P\. E. Bl\ |umulaut_o|\ chl, O. Jepsen, and O. K. Andersen, Phys. Rev. B **49**, 1450555 (1994).
.. [6] T\. Tadano and S. Tsuneyuki, Phys. Rev. B **92**, 054301 (2015).
.. [7] Y.\ Oba, T. Tadano, R. Akashi, and S. Tsuneyuki, Phys. Rev. Materials **3**, 033601 (2019).
27 changes: 21 additions & 6 deletions docs/source/input/inputanphon.rst
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Expand Up @@ -551,8 +551,8 @@ The first entry **KPMODE** specifies the types of calculation which is followed

=== ====================================================================================
0 Do not compute scattering phase space
1 Total and mode-decomposed scattering phase space involving three-phonon processes
will be stored in ``PREFIX``.sps
1 | Total and mode-decomposed scattering phase space involving
| the three-phonon processes will be stored in ``PREFIX``.sps
2 Three-phonon scattering phase space with the Bose factor will be stored
in ``PREFIX``.sps_Bose
=== ====================================================================================
Expand All @@ -568,8 +568,8 @@ The first entry **KPMODE** specifies the types of calculation which is followed

=== ====================================================================================
0 Do not compute the (atomic) participation ratio
1 Compute participation ratio and atomic participation ratio, which will be
stored in ``PREFIX``.pr and ``PREFIX``.apr respectively.
1 | Compute participation ratio and atomic participation ratio, which will be
| stored in ``PREFIX``.pr and ``PREFIX``.apr respectively.
=== ====================================================================================

:Default: 0
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=== =========================================================================
0 Do not consider phonon-isotope scatterings
1 Consider phonon-isotope scatterings
2 Consider phonon-isotope scatterings as in ``ISOTOPE = 1`` and
the corresponding selfenergy will be stored in ``PREFIX``.gamma_isotope
2 | Consider phonon-isotope scatterings as in ``ISOTOPE = 1`` and
| the calculated selfenergy is stored in ``PREFIX``.gamma_isotope
=== =========================================================================

:Default: 0
Expand All @@ -619,6 +619,21 @@ The first entry **KPMODE** specifies the types of calculation which is followed
This quantity is equivalent to :math:`g_{2}` appearing in the original paper by S. Tamura [Phys. Rev. B, 27, 858.].


````

* FE_BUBBLE-tag = 0 | 1

=== ====================================================================================
0 Do not compute the vibrational free-energy associated with the bubble diagram
1 | Compute the vibrational free-energy associated with the bubble diagram and
| save it in ``PREFIX``.thermo (when ``MODE = phonons``) or ``PREFIX``.scph_thermo (when ``MODE = SCPH``).
=== ====================================================================================

:Default: 0
:Type: Integer
:Description: This tag is used when *KPMODE* = 2.


````

* ANIME-tag = k1, k2, k3
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7 changes: 6 additions & 1 deletion docs/source/intro.rst
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Expand Up @@ -54,7 +54,7 @@ Anharmonic properties
* Phonon frequency shift due to 3- and 4-phonon interactions
* Temperature-dependent effective potential method
* Self-consisitent phonon (SCPH) calculation

* Anharmonic vibrational free-energy

Links
-----
Expand Down Expand Up @@ -88,6 +88,11 @@ If you use the self-consistent phonon (SCPH) method, please cite the following p
T\. Tadano and S. Tsuneyuki, Phys. Rev. B **92**\ , 054301 (2015).
[`Link <https://journals.aps.org/prb/abstract/10.1103/PhysRevB.92.054301>`__]

If you use ALAMODE to compute anharmonic vibrational free-energies in your research paper,
please cite the following paper as well:

Y\. Oba, T. Tadano, R. Akashi, and S. Tsuneyuki, Phys. Rev. Materials **3**\, 033601 (2019).
[`Link <https://journals.aps.org/prmaterials/abstract/10.1103/PhysRevMaterials.3.033601>`__]

Acknowledgement
---------------
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21 changes: 17 additions & 4 deletions docs/source/output.rst
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Expand Up @@ -9,20 +9,23 @@ Output files of alm

* ``PREFIX``.pattern_HARMONIC, ``PREFIX``.pattern_ANHARM?

In these files, displacement patterns are printed in units of :math:`\boldsymbol{e}_{x,y,z}`.
These files are created when ``MODE = suggest``.
In these files, displacement patterns are printed in units of
:math:`\boldsymbol{e}_{x,y,z}`.
These files are created when ``MODE = suggest``.
Patterns for anharmonic force constants are printed only when ``NORDER > 1``.

* ``PREFIX``.fcs

Harmonic and anharmonic force constants in Rydberg atomic units.
In the first section, only symmetry-reduced force constants are printed.
All symmetry-related force constants are shown in the following section with the symmetry prefactor (:math:`\pm 1`).
All symmetry-related force constants are shown in the following section
with the symmetry prefactor (:math:`\pm 1`).
Created when ``MODE = fitting``.

* ``PREFIX``.xml

A XML file containing necessary information for performing phonon calculations.
A XML file containing necessary information for performing
phonon calculations.
The files can be read by *anphon* using the ``FCSXML``-tag.
Created when ``MODE = fitting``.

Expand Down Expand Up @@ -54,6 +57,8 @@ Output files of anphon

Constant volume heat capacity, vibrational entropy, internal energy, and vibrational free energy.
Created when ``MODE = phonons`` with **KPMODE** = 2.
When ``FE_BUBBLE = 1`` is set in the **&analysis** field, an additional bubble correction term
to the vibrational free energy is also calculated.

* ``PREFIX``.msd

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Anharmonic phonon dispersion curves. The format is same as the ``PREFIX``.bands.

* ``PREFIX``.scph_thermo

Constant volume heat capacity, vibrational entropy, and vibrational free energy calculated
based on the self-consistent phononon calculation.
Created when ``MODE = SCPH`` with **KPMODE** = 2.
When ``FE_BUBBLE = 1`` is set in the **&analysis** field, an additional bubble correction term
to the vibrational free energy is also calculated.

* ``PREFIX``.scph_fc2_correction

This file contains :math:`\Delta D(\boldsymbol{q}) = D_{\mathrm{SCPH}}(\boldsymbol{q}) - D_{\mathrm{Harmonic}}(\boldsymbol{q})`.
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