[xkmax xkstep vixan]

E [aver [cross [relat]]]
kx ky kz
$\mathtt{\beta}$ $\mathtt{\alpha}$
nr na
dx dy


The maximum k-value for the calculation. xkmax, xkstep and vixan are exactly the same parameters as those used for the XANES and EXAFS cards.


The step size of the upper part of the k-mesh

The step size of the lower part of the k-mesh

energy of the electron beam in keV (typical values are 100-400 keV);

index 1: calculate orientation averaged spectrum (e.g., a polycrystalline sample, working at the magic angle) ; 0 to use specific sample to beam orientation (default);

1: use cross terms for the cross section (e.g., xy or yx ; default); 0: use only direct terms (eg., atom coordinates entered in symmetric coordinate frame ; assumed as default if aver is set to 1);

1 (default): to use relativistic formula for the cross-section (default, always recommended) ; 0 to use nonrelativistic formula (for checking against old results ; does not save any time!);

wave vector of the incoming electron in the crystal frame (i.e., the Cartesian coordinate system in which the atom positions of the ATOMS card are given); in arbitrary units (only the direction, not the size of k is used). This line should be present for orientation-sensitive calculations, and absent for averaged calculations.

the collection semiangle of the EELS detector in mrad (typical values are of the order of 1 mrad);

The convergence semiangle of the incoming beam in mrad (typical values are on the order of 1 mrad);
nr, na

The cross section is integrated over the values of q allowed by $\alpha$ and $\beta$; the integration grid consists of nr concentric circles sampling a disc of radius $\alpha$ + $\beta$; circle i contains $\mathtt{na}*(2\mathtt{i}-1)$ points, making for $\mathtt{nr}*\mathtt{nr}*\mathtt{na}$ points in total (this is a nonphysical parameter and should be converged; typical would be, e.g., 50, 1; the integration is quite fast ; only for small values of nr is it necessary to increase na above 1);
dx, dy

The position of the detector in the scattering plane, specified by angles in mrad along the x and y axes (the same as used in the ATOMS card) (typical values are 0.0, 0.0)

The line giving beam orientation must only be present when an oriented spectrum is calculated.