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Information card for entry 2101515
Preview
| Coordinates | 2101515.cif |
|---|---|
| Original IUCr paper | HTML |
| Formula | Bi2 Nb2 O9 Pb |
|---|---|
| Calculated formula | Bi2 Nb2 O9 Pb |
| Title of publication | Cation disorder in ferroelectric PbBi~2~Nb~2~O~9~ |
| Authors of publication | Srikanth, V.; Idink, H.; White, W. B.; Subbarao, E. C.; Rajagopal, H.; Sequeira, A. |
| Journal of publication | Acta Crystallographica Section B |
| Year of publication | 1996 |
| Journal volume | 52 |
| Journal issue | 3 |
| Pages of publication | 432 - 439 |
| a | 5.504 ± 0.003 Å |
| b | 5.487 ± 0.003 Å |
| c | 25.511 ± 0.005 Å |
| α | 90° |
| β | 90° |
| γ | 90° |
| Cell volume | 770.4 ± 0.6 Å3 |
| Number of distinct elements | 4 |
| Space group number | 36 |
| Hermann-Mauguin space group symbol | A 21 a m |
| Hall space group symbol | A -2 2a |
| Diffraction radiation probe | neutron |
| Diffraction radiation wavelength | 1.216 Å |
| Diffraction radiation type | neutron |
| Has coordinates | Yes |
| Has disorder | No |
| Has Fobs | No |
| Revision | Date | Message | Files |
|---|---|---|---|
| 198481 (current) | 2017-07-05 | cif/2/10/15/ (antanas@echidna.ibt.lt) Changing the space group from 'P -2 2a' to 'A -2 2a' in entries 2101514, 2101515 after consulting the original publication. All related space group information was changed accordingly. |
2101515.cif |
| 176432 | 2016-02-14 | cif/ (antanas@kurmis) Replacing _[local]_cod_* tags with their equivalents from the COD CIF dictionary in multiple entries. |
2101515.cif |
| 106285 | 2014-03-15 | cod/ (saulius@kolibris) Adding the '_diffrn_radiation_probe neutron' data item to those COD CIFs that declared neuron radiation in their _diffrn_radiation_type data field, and did not have a _diffrn_radiation_probe item yet: codsql 'select file from data where radiation is null and radType like "%neutron%"' -NB \ | codid2file \ | xargs -i sh -c 'test -f {} && ( set -x; echo _diffrn_radiation_probe neutron >> {} )' Two files that had no newlines at the end were fixed manually. |
2101515.cif |
| 91933 | 2013-12-28 | cif/ (saulius@koala.ibt.lt) Adding DOIs that could be assigned unambiguously to the range 2x CIFs. |
2101515.cif |
| 32112 | 2012-02-03 | cif/: committing an update of 45+ thous files, with information appended from the originals. | 2101515.cif |
| 26848 | 2011-09-28 | cif/2/, hkl/2/, html/ Reorganising CIFs of the range 2* into the "prefix-directory" tree. |
2101515.cif |
| 26029 | 2011-09-17 | cif/2/ Reverting changes of revision 25271: ( cd cif/2/; svn merge -r25271:25270 . ) The problem was that the reprocessed files from IUCr, although were more complete, "resurrected" data errors that were corrected in the previous recisions. The additional data that have been extracted during the reprocessing will have to be merged without overwriting the existing values in COD files, except some explicit and controlled cases (such as publication titles and chemical names). |
2101515.cif |
| 25271 | 2011-09-10 | cif/2/ Adding reporocessed IUCr CIFs for the years 1980-2010. The CIFs now contain more complete bibliography, substance names, correctly unfolded text fields (using the CIF line unfolding protocol), explicitely set cell angles, and _cod_data_source_block fields. |
2101515.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. |
2101515.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 |
2101515.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. |
2101515.cif |
| 340 | 2008-04-05 | Fixing CIF files headers in the CIF files from the Acta-Cryst-B/ retrospecive deposition. |
2101515.cif |
| 326 | 2008-04-03 | Adding all Acta Cryst. B, C, and E missing retrospective CIF files up to 2008 February, generated from the files that were automatically downloaded from the IUCr site. |
2101515.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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