Hi, I agree with Doeke, you are not the first to observe a deviation from coplanarity.
In https://doi.org/10.1016/S1074-5521(02)00112-6 you can find the following statement: "Nevertheless, examples have been described of magnesium adopting penta-covalent bonding with distorted trigonal bipyramidal geometry [23]." Reference/Review 23 is about magnesium compounds/constellations in crystallography: https://doi.org/10.1016/0022-328X(94)87036-5 A comparison between refined models with and without a coplanar constraint on the MgF3- is a first step to try and resolve the issue. Do not discard the „deviation from coplanarity" possibility a priori Cheers, Jeroen __ Dr. math. et dis. nat. Jeroen R. Mesters Biological Safety Officer (BBS) Deputy, Lecturer, Program Coordinator Infection Biology Visiting Professorship in Biophysics - University South Bohemia University of Lübeck Center for Structural and Cell Biology in Medicine Institute of Biochemistry Ratzeburger Allee 160 23562 Lübeck Tel +49 451 3101 3105 https://orcid.org/0000-0001-8532-6699 Am 03.02.2026 um 04:07 schrieb Hekstra, Doeke Romke <[email protected]>: Hi Friday, Perhaps nature disagrees with you! It may be that that water would like to turn this into something more tetrahedral :) Best, Doeke From: CCP4 bulletin board <[email protected]<mailto:[email protected]>> On Behalf Of Pavel Afonine Sent: Monday, February 2, 2026 9:44 PM To: [email protected]<mailto:[email protected]> Subject: Re: [ccp4bb] MgF3 not coplanar ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a mailing list hosted by www.jiscmail.ac.uk, terms & conditions are available at https://www.jiscmail.ac.uk/policyandsecurity/
