paramagpy.metal.Metal.first_invariant_squared

static Metal.first_invariant_squared(t)

Calculate the antisymmetric contribution to relaxation via the first invariant of a tensor.

This is required for PRE calculations using the shilding tensor

Parameters

tensor (3x3 matrix) – a second rank tensor

Returns

firstInvariantSquared – the first invariant squared of the shift tensor

Return type

float