Table 2. Programs used for refinement of STMV models and their capabilities.

	CNS		REFMAC5		SHELXL-97
Features	Available	Utilized	Available	Utilized	Available	Utilized
Simulated annealing	Yes	No	No	—	No	—
Conjugate-gradient minimization	Yes	Yes	Yes	Yes	Yes	Yes
Full least squares	No	—	No	—	Yes	No
NCS constraints	Yes	Yes	No	—	No	—
NCS restraints	Yes	Yes	Yes	Yes	Yes	Yes
Simultaneous refinement of positions and B factors	No	—	Yes	Yes	Yes	Yes
Positional restraints	Yes (harmonic)	Yes	No	—	Yes (DAMP)	Yes
Fixed atomic positions	Yes	Sometimes	No	—	Yes	Sometimes
Bulk-solvent correction	Yes	Yes	Yes	Yes	Yes	Yes
TLS refinement	No	—	Yes	Yes	No	—
Atomic anisotropic B/U-factor refinement	No	—	Yes	Yes	Yes	Yes
Blocked parameter refinement	Yes	Yes	No	—	Yes	Yes
Refinement against F or F 2	Both	Both	F	Yes	F 2	Yes
Maximum-likelihood target	Yes	Yes	Yes	Yes	No	—
Direct Fourier summation or fast Fourier (FFT)	Both	FFT	FFT	FFT	Direct	Direct