K-shell x-ray-production cross sections in ${}_6{}^{}{}_{}{}^{}\mathrm{C}$, ${}_8{}^{}{}_{}{}^{}\mathrm{O}$, ${}_9{}^{}{}_{}{}^{}\mathrm{F}$, ${}_{11}{}^{}{}_{}{}^{}\mathrm{Na}$, ${}_{12}{}^{}{}_{}{}^{}\mathrm{Mg}$, and ${}_{13}{}^{}{}_{}{}^{}\mathrm{Al}$ by 0.75- to 4.5-MeV protons

K-shell x-ray-production cross sections are reported for elements with K-shell x-ray energies between 277 eV (C) and 1487 eV (Al). The x-ray measurements were made with a windowless Si(Li) detector that was calibrated for efficiency by comparing bremsstrahlung spectra from electron bombardment of thin foils of aluminum, silver, and gold with theoretically determined bremsstrahlung spectral distributions. The x-ray-production cross-section measurements are compared to first-order Born and perturbed-stationary-state with energy-loss, Coulomb deflection, and relativistic corrections (ECPSSR) ionization theories using single-hole fluorescence yields. The ECPSSR and first-order Born theoretical predictions are, in general, in close agreement with each other and both generally fit the data quite well.