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Information card for entry 9000271
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| Coordinates | 9000271.cif |
|---|---|
| External links | AMCSD |
| Formula | Mg2 O4 Si |
|---|---|
| Calculated formula | Mg2 O4 Si |
| Title of publication | Computer-simulated crystal structures of observed and hypothetical Mg2SiO4 polymorphs of low and high density Model I |
| Authors of publication | Baur, W. H. |
| Journal of publication | American Mineralogist |
| Year of publication | 1972 |
| Journal volume | 57 |
| Pages of publication | 709 - 731 |
| a | 10.11 Å |
| b | 5.77 Å |
| c | 4.7 Å |
| α | 90° |
| β | 90° |
| γ | 90° |
| Cell volume | 274.173 Å3 |
| Number of distinct elements | 3 |
| Space group number | 10 |
| Hermann-Mauguin space group symbol | P 1 2/m 1 |
| Hall space group symbol | -P 2y |
| Has coordinates | Yes |
| Has disorder | No |
| Has Fobs | No |
| Revision | Date | Message | Files |
|---|---|---|---|
| 291269 (current) | 2024-04-18 | cif/9: Inserting Z values for entries in the 9 range |
9000271.cif |
| 282068 | 2023-03-26 | cod/ (saulius@tasmanijos-velnias) Adding the '_cod_related_entry_...' loop to those COD AMCSD entries that lacked it, and adding the related AMCSD database ID to this loop. |
9000271.cif |
| 282053 | 2023-03-24 | cod/ (saulius@tasmanijos-velnias) Updating the existing COD records from the recent AMCSD downloads: - Adding AMCSD IDs to those COD records that exacly matched the AMCSD structures (comparing unit cells, space groups, coordinates and measurement conditions) but did not yet have the AMCSD ID; - Adding new mineral names, compound sources, measurement conditions (when those were missing) and other informations from the AMCSD CIFs. |
9000271.cif |
| 176465 | 2016-02-16 | cif/ (antanas@kurmis) Replacing _[local]_cod_* tags with their equivalents from the COD CIF dictionary in multiple entries in range 9. |
9000271.cif |
| 85285 | 2013-05-05 | cod/ (saulius@koala.ibt.lt) Removing outdated _amcsd_database_code data items from all series 9 CIFs. |
9000271.cif |
| 77877 | 2013-03-29 | cod/ (saulius@koala.ibt.lt) Removing mineral names from those crystal structures that do not actually describe minerals (e.g. synthetic entries; data source: file COD-minerals.xlsx from my 2012-08-24 15:47 e-mail). |
9000271.cif |
| 77586 | 2013-03-28 | cod/cif/ (saulius@koala.ibt.lt) Merging mineral data updates (_chemical_name_mineral, _chemical_name_common, structural formulae) sent to me by T.D. in his e-mail. The merge was done by the command: for i in split/*.cif do ( B=$(basename $i); C=$(echo $B|awk '{print "/home/saulius/struct/cod/cif/"substr($0,1,1)"/"substr($0,2,2)"/"substr($0,4,2)"/"$0}'); ( set -x; cif_merge --over \ _chemical_name_mineral,_chemical_name_structure_type,_chemical_name_common,_chemical_name_systematic,_chemical_formula_structural,_chemical_formula_sum \ $C $i ) \ | cif_filter --add-cif-header $C \ | sponge $C ) done in the working copy of the following repository: URL: svn+ssh://pitonas.ibt.lt/home/xray/svn-repositories/xyz-extraction/contributions Repository Root: svn+ssh://pitonas.ibt.lt/home/xray/svn-repositories/xyz-extraction Repository UUID: 9acf3947-1f02-0410-ae2a-984b57ad209b Revision: 2625 Node Kind: directory Schedule: normal Last Changed Author: saulius Last Changed Rev: 2625 Last Changed Date: 2013-03-28 15:13:00 +0200 (Thu, 28 Mar 2013) |
9000271.cif |
| 35913 | 2012-02-28 | cif/9/ Reorganising range 9 into a prefix-directory tree. Range 9 is the last range to be reorganised. |
9000271.cif |
| 1210 | 2010-06-10 | cif/9/ Updating 13213 AMCSD CIFs, taking new data from the AMCSD database and adding the assigned AMCSD numbers. |
9000271.cif |
| 1071 | 2010-04-10 | cif/9/ Updating COD entries from AMCSD, processed in the AMCSD-resynchronisation-2009.06.24/ directory. Entries are updated if they could be unambiguously mapped to a unique COD number by automatic search scripts in AMCSD-resynchronisation-2009.06.24/. |
9000271.cif |
| 966 | 2010-01-30 | cif/ Adding _cod_database_code tags to all COD entries. Adding tag description to the cif_cod.dic dictionary so that COD entries can be validated. |
9000271.cif |
| 858 | 2009-11-18 | cod/cif/ Changing all _chemical_formula_sum values, were necessary, to conform IUCr recommended syntax and sorting order. After this operation, it will be easier to search for structures using the _chemical_formula_sum values. Only those files and thos lines that really needed to be changed were changed; otehrwise the CIFs were not reformatted. The procedure was as follows: first, all files were passed through a 'cif_filter --parse-formula-sum' command, and the lines containing _cif_formula_sum matching tags were extracted. The extracted tags were "spliced" into the CIF files using the ./bin/{un,}grepciftag commands and awk to filter out old tags and add new tags in their place; the replacement was only done if the new tags contained "_cod_" tags ('grep -q _cod_ tmp-$$'), indicating that cif_filter has altered the formula, or the original file did not contain the _chemical_formula_sum tag ('! grep -q _chemical_formula_sum X'), indicating that cif_filter has guessed the chemical_formula_sum from the file (which should not have happened, actually). If the file was different, disregarding spaces, from the original one ('if ! diff -wb X tmp2-$$'), the original was replaced by the new file, to be committed to the repository. The full command for this step was: ( \ set -x; \ find ? -name \*.cif \ | xargs -n1 -iX \ sh -c 'cif_filter --parse-formula-sum X \ | ./bin/grepciftag _chemical_formula_sum > tmp-$$; \ if grep -q _cod_ tmp-$$ || ! grep -q _chemical_formula_sum X; \ then \ awk "/^#/,/_chemical_formula_sum/{print} /_chemical_formula_sum/{exit}" X \ | ./bin/ungrepciftag _chemical_formula_sum > tmp2-$$; \ cat tmp-$$ >> tmp2-$$; \ awk "/_chemical_formula_sum/,/\$eof/" X \ | ./bin/ungrepciftag _chemical_formula_sum >> tmp2-$$; \ if ! diff -wb X tmp2-$$; \ then \ mv -fv tmp2-$$ X; \ fi; \ fi; \ rm -f tmp-$$ tmp2-$$' \ ) >& sort-chemical-formulae-2009.11.16.log Next, the files were searched that differ from their originals only by the order of CIF tags: svn st \ | awk '/^M/{print $NF}' \ | sort | xargs -n1 -iX \ bash -c 'if diff -q <(svn cat X|sort) <(sort X) >& /dev/null; \ then echo X; \ fi' \ >& only-reordered.lst These files, after manual inspection ('cat only-reordered.lst | xargs svn diff | less'), were reverted to the originals: cat only-reordered.lst | xargs svn revert Finally, a syntax check was performed using 'vcif': svn st | awk '/^M/{print $NF}' \ | sort | xargs -n1 -iX \ sh -c 'echo -n X"\r"; vcif -l 2048 X || { echo == X == ; echo X >&2; }' \ 2> vcif-check-2009.11.18.err A check on the whole COD archive showed the same files as recorded in vcif-check-2009.11.18.err: find ? -name \*.cif \ | sort \ | xargs -n1 -iX \ sh -c 'echo -n X"\r"; \ vcif -l 2048 X || { echo == X == ; echo X >&2; }' \ 2> vcif-all-check-`-date`.err diff vcif-check-2009.11.18.err vcif-all-check-2009.11.18.err Since no differences were detected in between vcif-check-2009.11.18.err and vcif-all-check-2009.11.18.err, the latter was deleted and is not committed. The check reveled two broken files, 2/2000267.cif and 2/2001000.cif; these were corrected manually. Afther this, one more 'vcif' check showed no syntax errors, and the changes are committed into the COD repository. 19798 files have modifications in this commit, according to svn st | grep '^M' | wc -l |
9000271.cif |
| 853 | 2009-11-16 | cif/ Reconstructing spacegroup designators from the symmetry operators were possible. The comands used can be found in the log file reformat-spacegroups-2009.11.14.log committed with the current revision. Only lines that contained spacegroup designators were changed, and all files pass vcif test after the conversion. |
9000271.cif |
| 255 | 2008-03-10 | Redepositing all AMCSD (9*series) COD CIF files. This redeposition regenerates AMCSD (9* series) files, 10011 entries total, from the original source CIF file cifdata.cif found on the CD received from Armel. Most importantly, the truncated formulas seem to be corrected. The files are not folded, i.e. they have lines longer than 80 characters (conforming CIF 1.1 specification, but not CIF 1.0 specification), and are otherwise syntactically correct. Some missing coordinates were fixed manually, restoring them from the AMCSD site, and non-ASCII symbols were fixed automatically during filtering. After the redeposition, the cifs-with-errors.lst was regenerated using the following command: find -name \*.cif \ | xargs -n1 -iI sh -c 'vcif -l 2048 I || echo I' \ | grep -vE 'CIF|ERR' \ | sort > cifs-with-errors.lst & |
9000271.cif |
| 19 | 2008-01-26 | Changing all end-of-line codes from DOS style to UNIX style in all COD CIF files, for more convenient processing: In the cod/cif/ directory: ff \*.cif | xargs perl -i -pe 's/\r\n/\n/' |
9000271.cif |
| 14 | 2008-01-14 | Appending a header with SVN keywords, COD URL and copying policy to all COD CIF files. |
9000271.cif |
| 13 | 2008-01-13 | Setting the svn:keywords property to "Author Date Revision URL Id" for all CIF files in the cod/cif directory. |
9000271.cif |
| 1 | 2007-11-30 | Adding all .cif files from the COD, downloaded in a Cod.zip file on 2007.02.07 (and the same Cod.zip is downloadable today, on 2007.11.29) |
9000271.cif |
All data in the COD and the database itself are dedicated to the
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Users of the data should acknowledge the original authors of the
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