For a quasi-Fuchsian group Γ with ordinary set Ω, and Δn the Laplacian on n-differentials on Γ\Ω, we define a notion of a Bers dual basis \documentclass[12pt]{minimal}
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\begin{document}$$\phi_{1},\dotsc,\phi_{2d}$$\end{document} for ker Δn. We prove that det\documentclass[12pt]{minimal}
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\begin{document}$$\Delta_{n}/\det \langle\phi_{j},\phi_{k}\rangle$$\end{document} , is, up to an anomaly computed by Takhtajan and the second author in (Commun. Math Phys 239(1-2):183–240, 2003), the modulus squared of a holomorphic function F(n), where F(n) is a quasi-Fuchsian analogue of the Selberg zeta function Z(n). This generalizes the D’Hoker–Phong formula det\documentclass[12pt]{minimal}
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\begin{document}$$\Delta_{n}=c_{g,n}Z(n)$$\end{document} , and is a quasi-Fuchsian counterpart of the result for Schottky groups proved by Takhtajan and the first author in Analysis 16, 1291–1323, 2006.