Crystallography Open Database

Information card for entry 2103918

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Coordinates	2103918.cif
Original IUCr paper	HTML
External links	ChemSpider

Structure parameters

Chemical name	Metal
Formula	Ta
Calculated formula	Ta
SMILES	[Ta]
Title of publication	The commensurate composite σ-structure of β-tantalum
Authors of publication	Arakcheeva, Alla; Chapuis, Gervais; Birkedal, Henrik; Pattison, Phil; Grinevitch, Vladimir
Journal of publication	Acta Crystallographica Section B
Year of publication	2003
Journal volume	59
Journal issue	3
Pages of publication	324 - 336
a	10.1815 ± 0.0005 Å
b	10.1815 ± 0.0005 Å
c	5.295 ± 0.0001 Å
α	90°
β	90°
γ	90°
Cell volume	548.9 ± 0.04 Å³
Cell temperature	120 ± 2 K
Ambient diffraction temperature	120 ± 2 K
Number of distinct elements	1
Space group number	81
Hermann-Mauguin space group symbol	P -4
Hall space group symbol	P -4
Residual factor for all reflections	0.0363
Residual factor for significantly intense reflections	0.0363
Weighted residual factors for significantly intense reflections	0.0501
Weighted residual factors for all reflections included in the refinement	0.0501
Goodness-of-fit parameter for all reflections included in the refinement	1.74
Diffraction radiation wavelength	0.70013 Å
Diffraction radiation type	synchrotron
Has coordinates	Yes
Has disorder	No
Has F_obs	No

Version history

Revision	Date	Message	Files
211196 (current)	2018-09-27	cod/ Removing the _chemical_name_common and _chemical_name_systematic data items that contained the summary chemical formula instead of the chemical name from 6249 entries.	2103918.cif
201972	2017-10-13	cif/ Marking COD entries in range 2/10 that are known to be related to ChemSpider entries using the _cod_related_entry data loop.	2103918.cif
176435	2016-02-14	cif/ (antanas@kurmis) Replacing _[local]_cod_* tags with their equivalents from the COD CIF dictionary in multiple entries from ranges 1, 2.	2103918.cif
91933	2013-12-28	cif/ (saulius@koala.ibt.lt) Adding DOIs that could be assigned unambiguously to the range 2x CIFs.	2103918.cif
26848	2011-09-28	cif/2/, hkl/2/, html/ Reorganising CIFs of the range 2* into the "prefix-directory" tree.	2103918.cif
20519	2011-06-11	smi/* and cif/* Adding SMILES for all structures with nel=1 in the mysql entries, supossed to be pure elements. For most of them, just the element symbol remains since SMILES strings and substructure search makes no sense for compact packed structures. Only for molecularly defined substances (for example cyclosulphur moieties) a proper SMILES string has been defined. This does not add too much funcionality to substructure search but flags a large number of structures as "SMILES done". Some of them were found to be not pure elements (carbides, boranes, hydrocarbons) but were added anyway. CIF files and SQL entries have been fixed for these as well as for other with obviously wrong formulas.	2103918.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.	2103918.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	2103918.cif
397	2008-06-20	Adding new CIF files deposited from Acta-Cryst-B-2001-2003/.	2103918.cif