This file should be readable by ReadRecord command, so the file structure is as follows (ordering of entries and empty lines are ignored):

```
# comment lines
SG=P21/c symmetry group recognized by SymmetryGroup command
orbs=[[1,3],[2,4]] optionally orbits of all sites (can be regenerated)
M=Matrix(3,3,[ matrix of translation vectors as columns
a,0,cx,
0,b,0,
0,0,c])
P=Matrix(3,ns,[ matrix of ns site positions in lattice coordinates as columns
2/3,1/3,x3,...
1/3,2/3,y3,...
0,0,z3,...])
geoparams=[ table of geometrical parameter sets, missing parameters are considered as zero
"cryst-b_PBE-D3paw600" ==[ a=7.708771, b=20.410479, cx=+0.743021, c=25.106085, x=0.735272, y=-0.497682, z=-0.018511],
"cryst-bx_PBE-D3paw600"==[ a=8.565262, b=20.081321, cx=-0.490141, c=25.555564, x=0.709776, y=-0.490029, z=-0.024840],
...
NULL]
params=[ table of Hamiltonian parameter sets, missing parameters are considered as zero
# optional description
"identifier" ==[ E0=-3.778, e1=-1.111, e2=2.222, t1=-2.887, t2=0.218, t3=-0.239, t3b=0.004, t4=0.046, t4b=-0.015, t5=0.001, t5c=-0.029, t5b=0.004],
# optional description 2
id2 ==list(equation), E0 is optional onsite energy offset
...
NULL]
H=[ translationally unique matrix elements of the Hamiltonian (preferably fully unfolded by symmetry)
(s0, s, t1, t2, t3)==H8, s0 is site index in the unit cell,
( 1, 2, -1, -2, 0 )==H3, [s,t1,t2,t3] denotes second site to which the matrix element is assigned,
( 1, 1, -3, -2, 0 )==H6, and t1,t2,t3 are integers encoding that site s is translated to other cell
( 1, 2, 0, 0, 0 )==t12,
( 1, 2, 1, -1, 0 )==t12aj,
( 1, 2, 2, -1, 0 )==t12aaj,
( 2, 1, -2, 1, 0 )==t12aaj,
( 2, 1, -1, 1, 0 )==t12aj,
( 2, 1, 0, 0, 0 )==t12,
...
NULL]
```