Absolute differential cross sections for elastic scattering of electrons from pyrimidine

Differential cross sections (DCSs) for elastic scattering of electrons from pyrimidine $\left({\text{C}}_4{\text{H}}_4{\text{N}}_2\right)$ are presented for incident energies from 50 to 300 eV. The measurements were performed using a cross beam technique, for scattering angles from $20°$ to $110°$. The relative DCSs were measured as a function of both the angle and incident energy and the absolute DCSs were determined using the relative flow method. The calculations of electron interaction cross sections are based on a corrected form of the independent-atom method, known as the screen corrected additivity rule procedure and using an improved quasifree absorption model. Calculated results agree very well with the experiment.

Figure 1

(Color online) Schematic drawing of pyrimidine molecule and pyrimidine nucleobases.

Figure 2

(Color online) Angular dependence of absolute differential cross sections for elastic electron scattering from pyrimidine at different incident energies. Full circles represent absolute experimental differential cross. Open stars represent absolute values obtained by relative flow method. The SCAR calculations are presented by full line and the SCARND by dashed line. The previous theoretical results for uracil [9] are presented by dotted curve.

Figure 3

(Color online) Energy dependence of absolute differential cross sections for elastic electron scattering from pyrimidine at the scattering angles of $50°$ and $100°$. Experimental differential cross sections (full circles) are normalized to the values extracted from the present absolute angle-differential cross sections (open diamonds). The SCAR calculations are presented by full line and SCARND by dashed line.