preferred_name: Li(+)(out) + 2 H(+)(in) => Li(+)(in) + 2 H(+)(out)
preferred_name_lc: li(+)(out) + 2 h(+)(in) => li(+)(in) + 2 h(+)(out)
label: Li(+)(out) + 2 H(+)(in) => Li(+)(in) + 2 H(+)(out)
label_lc: li(+)(out) + 2 h(+)(in) => li(+)(in) + 2 h(+)(out)