Powder dictionary (pdCIF) version 1.0.1
_pd_block_id
Name:'_pd_block_id'
Definition:
Used to assign a unique character string to a block. Note that this code is not intended to be parsed; the concatenation of several strings is used in order to generate a string that can reasonably be expected to be unique. This code is assigned by the originator of the data set and is used for references between different CIF blocks. The ID will normally be created when the block is first created. It is possible to loop more than one ID for a block: if changes or additions are made to the block later, a new ID may be assigned, but the original name should be retained. The format for the ID code is: <date-time>|<block_name>|<creator_name>|<instr_name> <date-time> is the date and time the CIF was created or modified. <block_name> is an arbitrary name assigned by the originator of the data set. It will usually match the name of the phase and possibly the name of the current CIF data block (i.e. the string xxxx in a data_xxxx identifier). It may be a sample name. <creator_name> is the name of the person who measured the diffractogram, or prepared or modified the CIF. <instr_name> is a unique name (as far as possible) for the data-collection instrument, preferably containing the instrument serial number for commercial instruments. It is also possible to use the Internet name or address for the instrument computer as a unique name. As blocks are created in a CIF, the original sample identifier (i.e. <block_name>) should be retained, but the <creator_name> may be changed and the <date-time> will always change. The <date-time> will usually match either the _pd_meas_datetime_initiated or the _pd_proc_info_datetime entry. Within each section of the code, the following characters may be used: A-Z a-z 0-9 # & * . : , - _ + / ( ) \ [ ] The sections are separated with vertical rules '|' which are not allowed within the sections. Blank spaces may also not be used. Capitalization may be used within the ID code but should not be considered significant - searches for data-set ID names should be case-insensitive. Date-time entries are in the standard CIF format 'yyyy-mm-ddThh:mm:ss+zz' Use of seconds and a time zone is optional, but use of hours and minutes is strongly encouraged as this will help ensure that the ID code is unique. An archive site that wishes to make CIFs available via the web may substitute the URL for the file containing the appropriate block for the final two sections of the ID (<creator_name> and <instr_name>). Note that this should not be done unless the archive site is prepared to keep the file available online indefinitely.Examples:
1991-15-09T16:54|Si-std|B.Toby|D500#1234-987 |
1991-15-09T16:54|SEPD7234|B.Toby|SEPD.IPNS.ANL.GOV |
May appear in list
Type: char
Category: pd_block