radtools.BCT_variation#

radtools.BCT_variation(conv_a: float, conv_c: float)[source]#

Two variations of the BCT lattice.

Condition \(a \ne c\) is assumed.

\(\text{BCT}_1: c < a\) and \(\text{BCT}_2: c > a\)

Parameters:
conv_afloat

Length of the \(a_1 == a_2\) vector of the conventional cell.

conv_cfloat

Length of the \(a_3\) vector of the conventional cell.

Returns:
variationstr

Variation of the lattice. "BCT1" or "BCT2".

Raises:
ValueError

If \(a == c\).