Spectral asymptotics of a strong δ′ interaction supported by a surface

We derive asymptotic expansion for the spectrum of Hamiltonians with a strong attractive δ′ interaction supported by a smooth surface in R3, either infinite and asymptotically planar, or compact and closed. Its second term is found to be determined by a Schrödinger type operator with an effective potential expressed in terms of the interaction support curvatures.