Equation Icon  [ 2 2 ]−1 f00 → − κ(a) + -ℏ-k-- (266 ) 4mnc [ 2 2 ]−1 j f0j → − κ(a) + -ℏ-k-- ∇-𝜃0- (267 ) 4mnc m i [ 2 2 ]−1 f i0 → − ∇-𝜃0- κ(a) + -ℏ-k-- (268 ) m 4mnc ij i [ 2 2 ]−1 j f ij → ncδ--− ∇-𝜃0- κ(a) + -ℏ-k-- ∇-𝜃0-. (269 ) m m 4mnc m