CASINO manual - Theory of Condensed Matter

2. The charge-density Fourier coefficients may be complex.
3. The EEPOT Fourier coefficients must be real (by definition).
4. This format allows for the existence of different types of particles.
5. Both the primitive-cell and simulation-cell translation vectors are included so that consistency
checks can be made. Furthermore, this allows the data to be scaled appropriately if they are
reused for a system of different size.
6. The normalization of the density should be such that the G = 0 component is equal to the
number of particles per primitive cell. This makes the density independent of simulation-cell
size.
Note: it is not necessary to regenerate this file for different supercell sizes, provided the lattice vectors
in the ‘EEPOT’ set are obtainable from the lattice vectors in [x]wfn.data through scaling by a single
parameter.
7.7 CASL files
7.7.1 The CASL file format
casino is starting to make use of the casl serialization language and file format for data interchange.
The casl serialization language defines a syntax to specify structured data by means of keywordvalue
associations. The file format is inspired by yaml, and is reminiscent of Python code in its use
of indentation.
A casl file, usually named filename.casl, could look like this:
keyword1: value1
keyword2: value2
keyword3:
keyword4: value4
keyword5: [ keyword6: value6, value7 ]
value8
where:
• keyword1 is the label of a scalar item of value value1.
• keyword3 is the label of a block item that contains the items labelled keyword4 and keyword5.
• keyword5 is the label of another block item, represented in-line using square brackets and commas,
that contains the item labelled keyword6 and an unnamed item of value value7.
• value7 and value8 are the values of two unnamed items. Unnamed items are intended to be
accessed by sequential order. Unnamed items cannot be block items.
casl keywords are case- and whitespace- insensitive. The : and , characters must have a whitespace
or newline immediately after them to be considered syntactically active.
The specific keyword-value structures available in a given casl block depends on the block, as described
below, but the underlying syntax is the same for all of them.
7.7.2 Compressed multi-determinant expansions: mdet.casl and cmdet.casl
casino will produce an mdet.casl file when runtype is set to gen mdet casl while using a multideterminant
expansion (see Sec. 7.4.4). This file describes the multi-determinant expansion (referring
to the orbitals as integer indices but not specifying what they are), and is used by the det compress
utility to produce a cost-efficient compressed version of the expansion.
The mdet.casl file looks like this:
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