On Fri, Feb 23, 2024 at 9:58 AM Winter, Graeme (DLSLtd,RAL,LSCI) < 00006a19cead4548-dmarc-requ...@jiscmail.ac.uk> wrote:
> While I get where you are coming from, it is still from a mathematical > standpoint correct to consider e.g. a tetragonal crystal as monoclinic - > P21 is a subgroup of P43212 (say) so strictly it is possible and correct - > if experimentally unlikely - to have the situation we are discussing here > occur. > Actually all values of beta are equally likely (up to a certain point, larger angles, say > 120, obviously become much less likely because it's likely that the cell can be transformed into one with a smaller angle). 90.0000 is just as likely as 90.0001, and 90.0002, and 90.0003 ... . If I ask what's the chance that the next structure determination in monoclinic will have beta = 91.2345 it's exactly the same chance as it will have beta = 90.0000 . Logically if we exclude 90.0000 on the grounds that it's very unlikely we should exclude all values! Obviously if I ask what's the chance beta will be _anything_ other than 90, that's a false comparison. 10 heads in a row has a chance of 2^-10 and so does any random sequence I name before the toss (say HHHTTHHTHT): the point is I'm doing the choosing. Cheers -- Ian ######################################################################## 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/
