Data-Driven Analysis of C–F Bond Lengths in Two-Dimensional Fluorinated Carbon Materials

The C–F bond length is an important structural descriptor of fluorinated carbon materials, but its reported values remain widely scattered across the literature. Here, a compilation and statistical analysis of C–F bond lengths is presented, focusing on two-dimensional (2D) fluorinated carbon materials and comparing them with fluorinated low-dimensional and molecular systems. The 2D dataset comprises 176 entries spanning C0.86F to C200F and covering publications from 1934 to 2026. It includes bulk, single-layer, and double-layer architectures, with carbon conformation in bulk structures also taken into account (e.g., puckered, planar, and mixed sp2/sp3). Mean C–F bond lengths decrease progressively from bulk graphite fluorides and fluorine–graphite intercalation compounds (~1.42 Å) to single- and double-layer fluorographenes (~1.40 and ~1.38 Å, respectively). They are generally longer than those of conventional molecular fluorides, fluorocarbonium ions and fluorocarbenium ions, but shorter than those in three-center fluoronium ions. Experimental determinations from the literature, including solid-state nuclear magnetic resonance and X-ray/neutron pair distribution function analysis, give broadly consistent mean bond lengths. Computational results from the literature likewise show broadly consistent values across exchange–correlation functionals. Decreasing fluorine content increases the mean C–F bond length by ~9% from ~1.39 Å for CF to ~1.51 Å for C16F. Puckeredchair structures generally show longer C–F bonds than puckered-boat structures, with a difference of ~0.04 Å in bulk materials. Together, these results provide an accessible reference that brings scattered C–F bond-length data together, revealing statistically supported trends that are difficult to identify from individual reports.