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CoH3 is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Co1+ is bonded to twelve equivalent H+0.33- atoms to form a mixture of face and corner-sharing CoH12 cuboctahedra. All Co–H bond lengths are 1.85 Å. H+0.33- is bonded in a square co-planar geometry to four equivalent Co1+ atoms.
CoH3 (CoH ver.3) is an optical model, exciton pre-equilibrium, and Hauser-Feshbach statistical model code, which calculates nuclear reaction cross sections for medium to heavy targets in the keV to MeV energy region. This program is written in standard C++, divided into approximately 200 source and header files. CoH solves the Schroedinger equation for optical potentials defined in the code, and calculates differential elastic scattering, reaction, and total cross sections, for neutron, proton, deuteron, triton, 3He, and alpha-particle. Deformed optical potentials are solved with the coupled-channels method, in which the ground state rotational band members, or vibrational phonon states are coupled. The optical model gives particle transmission coefficients that are fed into the statistical model calculations. CoH includes the pre-equilibrium model (exciton model), the direct/semidirect capture model, and the multi-stage Hauser-Feshbach statistical decay with width fluctuation correction based on the Gaussian orthogonal ensemble. For weakly coupled levels, the DWBA (distorted wave Born approximation) method is used to calculate the direct inelastic scattering process to the excited states.
Co(H(CN)2)3 crystallizes in the trigonal P-31m space group. The structure is zero-dimensional and consists of one cobalt molecule and three H(CN)2 clusters. In each H(CN)2 cluster, C+2.33+ is bonded in a single-bond geometry to one N3- atom. The C–N bond length is 1.17 Å. N3- is bonded in a linear geometry to one C+2.33+ and one H1+ atom. The N–H bond length is 1.27 Å. H1+ is bonded in a linear geometry to two equivalent N3- atoms.
CoH3(CO2)3CH3NH3 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional and consists of four methylammonium molecules and one CoH3(CO2)3 framework. In the CoH3(CO2)3 framework, Co2+ is bonded in an octahedral geometry to six O2- atoms. There are a spread of Co–O bond distances ranging from 2.09–2.18 Å. There are two inequivalent C1+ sites. In the first C1+ site, C1+ is bonded in a trigonal planar geometry to one H1+ and two equivalent O2- atoms. The C–H bond length is 1.11 Å. Both C–O bond lengths are 1.27 Å. In the second C1+ site, C1+ is bonded in a trigonal planar geometry to one H1+ and two O2- atoms. The C–H bond length is 1.11 Å. There is one shorter (1.27 Å) and one longer (1.28 Å) C–O bond length. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one C1+ atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one C1+ atom. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Co2+ and one C1+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one Co2+ and one C1+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Co2+ and one C1+ atom.
CoH3(CO2)3NH4 crystallizes in the hexagonal P6_3 space group. The structure is three-dimensional and consists of six ammonium molecules and one CoH3(CO2)3 framework. In the CoH3(CO2)3 framework, Co2+ is bonded in an octahedral geometry to six O2- atoms. There are a spread of Co–O bond distances ranging from 2.11–2.15 Å. There are three inequivalent C2+ sites. In the first C2+ site, C2+ is bonded in a trigonal planar geometry to one H1+ and two O2- atoms. The C–H bond length is 1.10 Å. There is one shorter (1.27 Å) and one longer (1.28 Å) C–O bond length. In the second C2+ site, C2+ is bonded in a trigonal planar geometry to one H1+ and two O2- atoms. The C–H bond length is 1.10 Å. There is one shorter (1.27 Å) and one longer (1.28 Å) C–O bond length. In the third C2+ site, C2+ is bonded in a trigonal planar geometry to one H1+ and two O2- atoms. The C–H bond length is 1.10 Å. There is one shorter (1.27 Å) and one longer (1.28 Å) C–O bond length. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one C2+ atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one C2+ atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one C2+ atom. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one Co2+ and one C2+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Co2+ and one C2+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Co2+ and one C2+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one Co2+ and one C2+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Co2+ and one C2+ atom. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to one Co2+ and one C2+ atom.
This project aims to provide the improved Evaluated Nuclear Data File (ENDF) using the newly measured data as well as the latest nuclear reaction model for calculating angular distributions and energy spectra on neutron-induced charged particle reactions through the collaboration of Korea Atomic Energy Research Institute (KAERI) and Los Alamos National Laboratory (LANL). The LANL group will provide the experimental data for angular distributions and spectra of (n,p) and (n,α) on several structural materials such as Fe, Ni and Zn isotopes using the Low Energy Neutron-induced Charged-particle (Z) Chamber (LENZ) instrument at Los Alamos Neutron Science Center (LANSCE). The KAERI group will provide the improved evaluated nuclear library which is based on the LANL experimental data, and further will predict angular distributions and spectra of (n,p) and (n,α) reactions on unmeasured nuclides, such as Cr, Mn, Co, Cu and so on. For the first year of this project, we planned to analyze (n,p) and (n,α) reactions for 54,56 Fe and perform new measurements on those reactions for 58,60 Ni isotopes with the LENZ instrument at LANSCE. For improving our evaluation quality, we have studied reaction models to reproduce LANL’s experimental angular distributions and energy spectra using the full Hauser-Feshbach model code, CoH3 with no approximations used. As the first year’s deliverables, we provided the experimental (n,p) and (n,α) reaction cross sections for 54,56 Fe and incorporate new evaluation on angular distributions and energy spectra of neutron-induced charged particle reactions into the current ENDF/B-VIII.0.