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.