Dear Armel,


below please find my solution for UPPW-2. I dont like it but it indexes at least all the first 35 lines (I didnt check more lines because I am in a hurry) with 2theta deviations less than 0.04? As I am right now in Nanning/China without being able to connect my own PC to internet, I cant send more details. 


Software: TOPAS, SVD-Index approach


Sg  UNI Vol Gof Zero    a   b   c   al  be  ga
1   P-1 0   649.284 49.49   0.0000  4.1796  10.6946 14.6940 83.8920 93.6490 85.4440


For the upcoming (and certainly even more complex) UPPW challenges I would love to have the ability to look at the powder patterns as well, exactely because of the same reasons Peter Stephens mentioned recently. For the first e.g. 20 d-values of UPPW-2 I can also identify a couple of other, even hexagonal cells (with significantly larger volumes though), with all observed and calculated lines indexed. Without being able to validate the d-values supplied, i.e. without being able to do my own peak search, and to do WPPD this is no fun. Thats why I dont like my solution for UPPW-2 in principle, there is too much ambiguity.


Cheers,


Arnt