J = 0 – L & S parallel and pointing in the opposite direction (J = L + S = 0)
L & S vectors point in the opposite direction with the same magnitude -> resulting vector is 0;
J = 2 – L & S parallel and pointing in the same direction (J = L + S = 2)
L & S vectors point in the same direction with the same magnitude -> resulting vector is 2;
J = 1 – L & S perpendicular to each other (J = L + S = 1*cos90 + 1*cos0)
L & S vectors point in the perpendicular direction with the same magnitude -> resulting vector is 1 due to geometric orientation with respect to the atom’s rotational axis (z-axis). Any combination of angles will in perpendicular case lead to sinusoidal dependency on the vector sum to be 1;