On the reaction of a uranium atom with a nitrogen molecule: a theoretical attempt

Abstract

An attempt has been made to study the reaction between a uranium atom and a nitrogen molecule theoretically using multiconfigurational wave functions. The C 2v part of the reaction surface has been computed for several electronic states of various spin multiplicities. The system proceeds from a neutral uranium atom in its (5f) 3 (6d)(7s) 2 , 5 L ground state to the linear molecule NUN, which has a 1 S þ g ground state and uranium in a formal U(VI) oxidation state. The effect of spin-orbit coupling has been estimated at crucial points along the reaction. These preliminary results shows that the system proceeds from a quintet state for U + N 2 , via a triplet transition state to the final closed shell molecule. An eventual energy barrier for the insertion reaction is caused by the spin-orbit coupling energy.

Experimental and Theoretical Evidence for U(C6H6) and Th(C6H6) Complexes

“…This approach has been shown to work successfully in a number of earlier applications. [33][34][35][36][37] In the present calculation, the roots of all states (of all possible spins and symmetries) lying up to 0.65 eV (15 kcal/mol) from the lowest state were selected.…”

Multiconfigurational quantum chemical methods for molecular systems containing actinides

“…21,22 The OUO molecule was found to have a (5f w)(7s), The reaction between a uranium atom and a nitrogen molecule N 2 leading to the formation of the triatomic molecule NUN was also studied. 25 The system proceeds from a neutral uranium atom in its (5f) 3 (6d)(7s) 2 , 5 L ground state to the linear molecule NUN, which has a 1 S þ g ground state and uranium in a formal U(VI) oxidation state. The effect of spinorbit coupling has been estimated at crucial points along the reaction.…”

Effects of density functionals and dispersion interactions on geometries, bond energies and harmonic frequencies of EUX3 (E=N, P, CH; X=H, F, Cl)

“…The isolation of terminal uranium nitride species [N"U@NH], [N"U@O] + , [N"U"N], and [N" UF 3 ] has been achieved by inert gas matrices at lower temperatures [1][2][3] [5]. A number of theoretical studies have been carried out for uranium compounds containing triple bonds between uranium and main group elements [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22]. The calculated U"E bond distances at various level of theory are summarized in Table 1 3 ] at CASPT2 level indicate that the more electronegative substituents lengthen the U"N bond distance.…”