  In this work we analyze F-theory and Type IIB orientifold compactifications
to study $\alpha '$-corrections to the four-dimensional, $\mathcal{N} = 1$
effective actions. In particular, we obtain corrections to the K\"ahlermoduli
space metric and its complex structure for generic dimension originating from
eight-derivative corrections to eleven-dimensional supergravity. We propose a
completion of the $G^ 2 R^3$ and $(\nabla G)^2R^2$-sector in eleven-dimensions
relevant in Calabi--Yau fourfold reductions. We suggest that the
three-dimensional, $\mathcal{N}=2$ K\"ahler coordinates may be expressed as
topological integrals depending on the first, second, and third Chern-forms of
the divisors of the internal Calabi--Yau fourfold.
  The divisor integral Ansatz for the K\"ahler potential and K\"ahler
coordinates may be lifted to four-dimensional, $\mathcal{N} = 1$ F-theory
vacua. We identify a novel correction to the K\"ahler potential and coordinates
at order $ \alpha'^2$, which is leading compared to other known corrections in
the literature. At weak string coupling the correction arises from the
intersection of $D7$-branes and $O7$-planes with base divisors and the volume
of self-intersection curves of divisors in the base. In the presence of the
conjectured novel $\alpha'$-correction resulting from the divisor
interpretation the no-scale structure may be broken. Furthermore, we propose a
model independent scenario to achieve non-supersymmetric AdS vacua for
Calabi-Yau orientifold backgrounds with negative Euler-characteristic.
