For example: gto.basis.load("6-31g", "Li")
will show:
[[0,
[642.41892, 0.0021426],
[96.798515, 0.0162089],
[22.091121, 0.0773156],
[6.2010703, 0.245786],
[1.9351177, 0.470189],
[0.6367358, 0.3454708]],
[0, [2.3249184, -0.0350917], [0.6324306, -0.1912328], [0.0790534, 1.0839878]],
[0, [0.035962, 1.0]],
[1, [2.3249184, 0.0089415], [0.6324306, 0.1410095], [0.0790534, 0.9453637]],
[1, [0.035962, 1.0]]]
This is a list with 5 elements (which are also lists). The first element of each of these 5 lists represents angular momentum. In this example, there are 3 lists starting with a 0; how does pyscf determine if the list of [exponent, coefficient]
that follow are for the 1s or 2s orbitals?