The rotations identified in the rotation search are applied to the search molecule and the translational position in the unit cell is determined. Only those rotation peaks which produce a significant translation function peak will be considered to be correct. Before and after the translation search the roational orientation of the search model is optimized by Patterson-Correlation (PC) refinement. All of these procedures are localized in the CNS task file translation.inp. Translation searches are performed for the top 10 cross rotation peaks.
cns_solve < translation.inp > translation.out [4 minutes]
The translation search produces a listing which details the rotational parameters for the search model after final PC refinement, the translation of the molecule (in orthogonal Å), the value of the translation search scoring function, and the packing value (this the percentage of the unit cell covered by the molecule):
theta1 theta2 theta3 transX transY transZ monitor packing
R# 1 64.18 78.34 77.73 3.25 18.21 21.25 0.286 0.3482
R# 2 63.58 54.79 47.73 15.45 13.83 17.19 0.204 0.3514
R# 3 73.58 65.33 30.86 29.49 20.34 8.16 0.186 0.3435
R# 4 224.63 88.24 206.15 8.46 6.38 2.23 0.194 0.3517
R# 5 62.52 43.52 81.39 22.08 32.82 16.14 0.184 0.3004
R# 6 53.45 79.60 325.63 15.40 3.10 20.23 0.193 0.3413
R# 7 43.10 66.39 46.80 12.02 12.47 20.20 0.195 0.3526
R# 8 30.54 7.28 313.73 12.17 11.83 3.42 0.229 0.3526
R# 9 54.17 71.61 314.12 7.96 30.77 3.10 0.208 0.3526
R# 10 54.47 84.47 45.50 31.57 11.24 20.84 0.201 0.3528
There is one solution with a correlation coefficient (in this case E2E2) which is significantly higher than all other solutions (0.286 with the next closest peak 0.229). The packing value is also high, indicating minimal overlap of the molecule with itself. The translation search writes out rotated and translated coordinates for all rotation peaks tested. The solution with the highest correlation coefficient is also written out as the best answer. In this example the top rotation solution peak corresponds to a correct orientation for the molecule. This is not always the case and several rotation solutions may need to be tested to find a correct translation solution. It is feasible to test many rotation solutions because of the fast translation search. In difficult cases it may be useful to test all peaks found in the cross-rotation search.