Structures and heats of formation of simple alkaline earth metal compounds: fluorides, chlorides, oxides, and hydroxides for Be, Mg, and Ca.
Geometry parameters, frequencies, heats of formation, and bond dissociation energies are predicted for the simple alkaline earth (Be, Mg and Ca) fluorides, chlorides, oxides, and hydroxides at the coupled cluster theory [CCSD(T)] level including core-valence correlation with the aug-cc-pwCVnZ basis sets up to n = 5 in some cases. Additional corrections (scalar relativistic effects, vibrational zero-point energies, and atomic spin-orbit effects) were necessary to accurately calculate the total atomization energies and heats of formation. The calculated geometry parameters, frequencies, heats of formation, and bond dissociation energies are compared with the available experimental data. For a number of these alkaline earth compounds, the experimental geometries and energies are not reliable. MgF(2) and BeF(2) are predicted to be linear and CaF(2) is predicted to be bent. BeOH is predicted to be bent, whereas MgOH and CaOH are linear. The OBeO angle in Be(OH)(2) is not linear, and the molecule has C(2) symmetry. The heat of formation at 298 K for MgO is calculated to be 32.3 kcal/mol, and the bond dissociation energy at 0 K is predicted to be 61.5 kcal/mol.
Vasiliu
Monica
M
Chemistry Department, Shelby Hall, The University of Alabama, Shelby Hall, Box 870336, Tuscaloosa, Alabama 35487-0336, USA.
Feller
David
D
Gole
James L
JL
Dixon
David A
DA
D001608:Beryllium / Q000737:chemistry; D002118:Calcium / Q000737:chemistry; D002712:Chlorides / Q000737:chemistry*; D005459:Fluorides / Q000737:chemistry*; D006358:Hot Temperature; D006878:Hydroxides / Q000737:chemistry*; D008274:Magnesium / Q000737:chemistry; D008673:Metals, Alkaline Earth / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D013816:Thermodynamics
D002712:Chlorides; D006878:Hydroxides; D008673:Metals, Alkaline Earth; D010087:Oxides; D008274:Magnesium; D001608:Beryllium; D005459:Fluorides; D002118:Calcium