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[sdpd] Re: No news from DASH, ex-DRUID ?

Lachlan wrote :

>If the main(?) problem people encounter with solving from
>powders is reliable powder indexing - what percentage will
>ever get through to trying solve using programs such as DASH.
>(the above Round Robin was on a phase where the cell was given -
>as it was a "solving" round robin - not an indexing round robin)

There is a new SDPD Round Robin equivalent running
right now. It is continuously open, but with registration
fees ;-) the SDPD Internet Course at :
   http://www.cristal.org/course/
Students have several unknowns so solve, week after week,
including each step, indexing as well, of course. No trace
of the materials in the databases.

I would not say that indexing is the main problem. It is one
of the main problem, its peculiarity is that it is occurring first.
No solution at this step and you cannot pursue your quest.
But I think that no indexing with the 8 programs in Crysfire
means generally that the data are too bad versus the complexity
level. An experienced eye may see at once that little chance
is expectable from some poorly resolved powder patterns.

>Most existing programs are "find the peaks yourself" then try
>out an indexing program/or suite - such as Crysfire, Winplotr,
>Powder v2.00, PowderX, etc.
>
>The only "available" exception seems to be the EFLECH/INDEX 
>(fundamental parameters fitting) written by Joerg Bergmann -

Well, I belong to the old school, quite happy with the old good
standard programs. EFLECH was said by the author to be extremely
slow. I tested it and agree that you should be prepared to wait a lot.
Has this inconvenience been overcome ?

Can we expect that the IUCr CPD organize a second SDPD 
Round Robin some day ? A complete one, preferably. The first
shown that the SDPD community was rather unarmed to face
problems at the limit of the feasible (with a complexity/resolution
ratio >1), but it should be noted that a lot of old experienced guys
in the field simply did not participated...

Best,

Armel