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Re: Proposal to define data names for atomic analysis information

The discussion on GitHub is nice, and an appropriate location forrefining the details (e.g. distinguishing between isotopes, valencestates etc.)
As Peter M-R responded, the second alternative seems the preferableapproach as it makes explicit the specific parameters important foreach different technique. As Matthew Rowles points out in the GitHubdiscussion, each individual technique may have looped parameters,and so is going to be characterised by a distinct category.
By eye, it's "obvious" that the _atom_analytical.technique_typevalue of "XRF" is intended as a pointer into the categoryATOM_ANALYTICAL_XRF that includes
_atom_analytical_XRF.mass_loss_percent    12.4
because of that shared occurrence of the string "XRF". But strictly,category and data names have no intrinsic semantic meaning. Is therea formal mechanism in the DDL to allow the value of a data item to beunderstood as a pointer to a specific category, and if not, doesthere need to be?
It's possible that there doesn't need to be, since in the full example as worked out on GitHub, the links between the categories are followedthrough the *.id and *.meas_id codes:
loop__atom_analytical.atom_type_atom_analytical.meas_id # <- point to atom_analytical_source.id_atom_analytical.chemical_species_atom_analytical.analytical_mass_percent_atom_analytical.chemical_species_mass_percentSi  a SiO2   ?     22.7Al  a Al2O3  ?     27.4Ti  b TiO2   ?      2.7Si  c  .      10.5  .Si  d Si     11.7  11.7
loop__atom_analytical_source.id_atom_analytical_source.techniquea  XRFb  XRFc  ICPd  EDS
loop__atom_analytical_XRF.meas_id # <- point to _atom_analytical_source.id_atom_analytical_XRF.mass_loss_percent_atom_analytical_XRF.ignition_temperaturea 12.4 1000b 13.5 1100
Arguably the middle loop is redundant, and the use of (say) XRF isdeduced from the fact that you have ended up in a category that willbe defined as applicable only for XRF measurements; but in practiceI assume that having a synoptic overview of the different techniquesused would be welcomed by most users.
On 04/10/2022 02:43, James H via coreDMG wrote:> Dear Core CIF dictionary maintenance group:> > A proposal has been developed by some powder people to include results > of sample analysis for atomic content in CIF files. It seems to me that > this is more general than just powder, so I have transferred to proposal > to the CIF core dictionary issues list. Please read through > https://github.com/COMCIFS/cif_core/issues/304 > <https://github.com/COMCIFS/cif_core/issues/304> and add your comments > there or here. For reference, the final comment on that issue, which > gives the flavour of the proposal, is reproduced below.> > best wishes,> James.> =================================> > Given the desire to allow general details of techniques to be included, > we will need one or more separate categories. One alternative is to > bundle all details of techniques into a general purpose category, in the > example below it is |ATOM_ANALYTICAL_TECHNIQUE|> > Here is an example of how this would appear in the CIF file (adapted > from above):> > |data_block1 loop_ _atom_analytical.id <http://atom_analytical.id> > _atom_analytical.atom_type _atom_analytical.chemical_species > _atom_analytical.analytical_mass_percent > _atom_analytical.chemical_species_mass_percent > _atom_analytical.technique_id #<- refers to an > _atom_analytical_technique.id <http://atom_analytical_technique.id> 1 Si > SiO2 ? 22.7 XRF 2 Al Al2O3 ? 27.4 XRF 3 Ti TiO2 ? 2.7 XRF 4 Si . 10.5 . > ICP 5 Si Si 11.7 11.7 EDS loop_ _atom_analytical_technique.id > <http://atom_analytical_technique.id> #<- this could be a run id if more > than one performed _atom_analytical_technique.type #XRF/ICP/EDS etc. > _atom_analytical_technique.special_details XRF XRF ; The loss on > ignition at 1000 °C was 12.4 wt% ; #... |> > The other alternative, and the one most conducive to expansion in the > future, is to define categories for each analytical technique. These can > remain largely empty until others want to fill them in. So the above > would become:> > |loop_ _atom_analytical.id <http://atom_analytical.id> > _atom_analytical.atom_type _atom_analytical.chemical_species > _atom_analytical.analytical_mass_percent > _atom_analytical.chemical_species_mass_percent > _atom_analytical.technique_type 1 Si SiO2 ? 22.7 XRF 2 Al Al2O3 ? 27.4 > XRF 3 Ti TiO2 ? 2.7 XRF 4 Si . 10.5 . ICP 5 Si Si 11.7 11.7 EDS > _atom_analytical_XRF.mass_loss_percent 12.4 > _atom_analytical_XRF.ignition_temperature 1000 |> > Of these I strongly prefer the second as it ensures that the minimum > amount of information is hidden in machine-opaque text.> > -- > T +61 (02) 9717 9907> F +61 (02) 9717 3145> M +61 (04) 0249 4148> > _______________________________________________> coreDMG mailing list> coreDMG@iucr.org> http://mailman.iucr.org/cgi-bin/mailman/listinfo/coredmg_______________________________________________coreDMG mailing listcoreDMG@iucr.orghttp://mailman.iucr.org/cgi-bin/mailman/listinfo/coredmg

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