[sharp-discuss] Space group I2

[Phil Evans]

1. It is the IUCr "standard" if it gives a smaller beta angle than C2
2. You may get a less oblique cell (in our case close to 90deg) so when coot selects a block of map it looks more sensible
3. very oblique cells may lead to interpolation errors, if not done correctly
4. there are cases which are I2 but pseudo-I222, and this makes their relationship clear
5. all (nearly all) other programs support it
6. it is a standard space group
7. there shouldn't be any difficulty in supporting it

Same goes for eg P 2 21 21  etc

Phil

On 12 Aug 2011, at 10:02, Clemens Vonrhein wrote:

> Hi Phil,
> 
> On Thu, Aug 11, 2011 at 10:39:59PM +0100, Phil Evans wrote:
>> Sharp seems to fail in space group I2 - is this a known bug?
> 
> It's very possible - we usually run in 'standard' spacegroups, so C2
> instead of I2.
> 
> If there is a strong reason for supporting I2 on top of C2, please let
> us know and we'll find a dataset for testing this.
> 
> Cheers
> 
> Clemens
> 
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