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Re: CIF dictionary for Restraints and constraints

Title:
Dear Brian,

Thanks for running the restraints dictionariy through vcif.  I was hoping you would do this.  Someday I will have to work out how to use vcif myself..

We will take note of your comments.  There is one that needs an immediate comment to avoid unnecessary confusion.
Brian wrote:
I note the use of 'esd' and 'estimated standard deviation', where the core
dictionary has systematically replaced such phrases with 'standard
uncertainty'.

Response:
Apart from type_coonditions where I failed to notice that 'su' is a legitimate value (or I would have used it), the use of 'esd' is deliberate, since in these cases it does not refers to the standard uncertinaty but to the estimated standard deviation between a set of values and their average.  The ambiguity between these two definitions of esd was what led to the adoption of su to describe experimental uncertainty, so that we can now use esd as a statistical term in the way it was intended.
David 
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fn:I.David Brown
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org:McMaster University;Brockhouse Institute for Materials Research
adr:;;King St. W;Hamilton;Ontario;L8S 4M1;Canada
email;internet:idbrown@mcmaster.ca
title:Professor Emeritus
tel;work:+905 525 9140 x 24710
tel;fax:+905 521 2773
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