view article
Figure 4
Illustration of R1(F) from SHELXL refinements with BODD aspherical scattering factors (light blue dots). A penalty ΔR1(F) from enforcing tight structure-specific restraints (s.u. = 0.0005 Å for bonds, s.u. = 0.002 Å for angles) from QM:MM APFD 6-31G(d,p):UFF MIC optimizations without (blue) and with (orange) C-PCM solvent embedding is shown. Using C-PCM leads to better agreement for most zwitterions; earlier compounds with high discrepancies in SQM disappear.

IUCrJ
Volume 12| Part 4| July 2025|
ISSN: 2052-2525
https://doi.org/10.1107/S2052252525004543