band_structure: evaluates a 4D S(q,w) model along specified k-path / bands band_structure(f, kpath, w, options) The k-path can be given as a cell containing 3-values (HKL) vectors, or a n x 3 matrix, each row being a HKL location. The energy range can be entered as a vector, or a [min max] pair. Refer to https://en.wikipedia.org/wiki/Brillouin_zone and http://lamp.tu-graz.ac.at/~hadley/ss1/bzones/ to get the standard points in the Brillouin zone. The bands intensity is computed along the path. For neutron scattering, as all standard points in the Brillouin zone are centered around 0 and the intensity is proportional to |Q.e|^2, all transverse modes are extinct. To get the proper band intensity around a given Bragg peak G, the k-path should be shifted by G. band_structure(f); plots the dispersion curves following the BZ points for the crystal spacegroup, and using the maximum excitation energy. [S,k] = band_structure(...) returns the dispersion curves data set (iData), and the k-path used. When the command is followed by ';' or options contains 'plot', a plot is generated. Example: S = band_structure(sqw_cubic_monoatomic, '', [0 10]); plot(log10(S)); S = sqw_phonons('POSCAR_Al','emt','metal'); band_structure(S); input: f: a 4D HKLE model S(q,w) (iFunc) path: a list of k-locations given as a cell/array of HKL locations (cell or matrix) can also be 'Cubic','Hexagonal','Trigonal','Tetragonal','Orthorhombic', 'Monoclinic','Triclinic','fcc','bcc' can also be given as a list of BZ points, such as: {'Gamma' 'K' 'M' 'Gamma' 'A' 'H' 'L' 'A' } which are then defined according to the space group, e.g: f.UserData.properties.spacegroup_number can be given as a list of HKL locations, such as {[0,0,0],[1,1,1],[1,1,0]} or as an array e.g. [0 0 0 ; 1 1 1 ; 1 1 0 ; 0 0 0 ; 0 0 1] The path can also be given as a Bragg peak location, e.g. [0 0 1] to compute the dispersion around that location using the default K-path in the BZ. when not given or empty, this is guessed from the crystal spacegroup. w: a vector of energies (4-th axis) for which to evaluate the model (double) can also be given as Emax, or [ Emin Emax ] when not given or empty, the maximum excitation energy is used. options: plotting option (string). Can contain 'plot' 'THz','cm-1','meV'. The 'plot' option also displays the density of states, when available. The 'newplot' option does the same but opens a new figure instead of re-using an existing one. output: S: the dispersion W(HKL) computed along the path (iData) k: the k-path used to generate the dispersion curves (matrix, HKL list) fig: figure handle generated when options contains 'plot' or no output. Version: Nov. 26, 2018 See also sqw_cubic_monoatomic, sqw_sine3d, sqw_vaks, sqw_spinw iFunc_Sqw4D/powder, <a href="matlab:doc(iFunc,'Models')">iFunc:Models</a> (c) E.Farhi, ILL. License: EUPL.

- band_structure band_structure: evaluates a 4D S(q,w) model along specified k-path / bands
- dos iFunc_Sqw4D: dos: compute the density of states (vDOS)
- max iFunc_Sqw4D: max: get a quick estimate of the max dispersion frequency

- band_structure band_structure: evaluates a 4D S(q,w) model along specified k-path / bands
- iFunc_Sqw4D

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