The map p(o) was calculated with coefficients 2F(o) - F(c) and with phase alpha(c). F(o) are the observed structure factor amplitudes, F(c) are the amplitudes calculated from the current model and alpha(c) are the phases calculated from the current model. The map p(c) was calculated in program O using a Gaussian distribution function around the atoms in the current model. Map grid points within 1.5 A of the designated atoms were included in the calculation.
The map p(o) was calculated with coefficients F(o) and with phase alpha(c). F(o) are the observed structure factor amplitudes, and alpha(c) are the phases calculated from the current model. The map p(c) was calculated with coefficients F(c) and with phases alpha(c). F(c) and alpha(c) are the structure factor amplitudes and phases, respectively, calculated from the current model. Map grid points within a van der Waals radius of the designated atoms were included in the calculation.