Now let us go to the bond l − − 1 and calculate the norm of the right-hand Schmidt vectors ‖ ‖ Φ Φ α α l − − 1 [ l − − 1.. N ] ‖ ‖ ; taking into account the full Schmidt dimension, the norm is: n 1 = 1 = ∑ ∑ α α l = 1 χ χ c ( c α α l − − 1 α α l ) 2 ( λ λ α α l [ l ] ) 2 + ∑ ∑ α α l = χ χ c χ χ ( c α α l − − 1 α α l ) 2 ( λ λ α α l [ l ] ) 2 = S 1 + S 2 ,