., N 2 O, N 2 O + CO N 2 + CO 2 (1) N 2 O +M + N 2 +MO + (2) MO + + CO M + + CO 2 (3) FeO + /FeO + ] (OFeO + ) ) +

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1 Vol. 29 No CHEM ICAL JOURNAL OF CH INESE UN IVERSITIES FeO + ( 6 + ) CO N 2 O,,, (,, ) B3LYP / G(2d) / /B3LYP /6231G( d), FeO + ( 6 + ) CO N 2 O., FeO + ( 6 + ), N 2 O O, CO,., [ Fe (O 2 ) + ] (OFeO + ),,. FeO + ; ; N 2 O O641 A (2008) N 2 O ( )., N 2 O, GW P ( GlobalW arm ing Potential) CO 2 296, [ (120 30) ]., N 2 O, NO x,, [ 1 ]., N 2 O [ 2, 3 ]. [ 4 ], CO N 2 O : N 2 O ( H f N 2 O + CO N 2 + CO 2 (1) = 8710 kj /mol) [ 5 ], CO ( r H = kj /mol) [ 5 ],, ( kj /mol) [ 6 ], ( > 1000 K). Kappes Staley [ 7 ], M +, Fe +,. : M + N 2 O O MO +, CO,, (2) (3) : N 2 O +M + N 2 +MO + (2) MO + + CO M + + CO 2 (3), M + O, Fe + BE ( Fe + O ) BE (NN O) BE (OC O)., Bohme [ 8 ], 26 M +, 10,, (2) (3)., [ 9, 10 ]., M + /MO +, MO + /MO + 2 [ 7, 8, 11 ].,, Fe2ZSM 25 N 2 O [ 12 ]. Bell [ 13 ] EXFAS Fe2ZSM 25 Fe, FeO + /FeO + 2. [ 14 ], MO + 2 : ( ) ; ( ) ; ( ). Schwarz [ 15 ], FeO + 2, CASSCF ( 6 A 1 ) ( 6 A 1 ) kj /mol, CASPT2D 2019 kj /mol. Bell [ ] Fe2ZSM 25 N 2 O C H,,. : : ( : 2005CB221408) ( : , ). :,,,,,. hlwan@ xmu. edu. cn

2 2366 Vol. 29 (B3LYP), OFeO + Fe (O 2 ) + CO N 2 O. 1 B3LYP / G (2d) / /B3LYP /6231G ( d) [ 19, 20 ], 6231G ( d),, B3LYP / G (2d). B3LYP /6231G( d) ( ZPE)., ( r H) N 2 O ( f H), ( 1). 1,, 4 kj /mol. NBO [ 22 ]. Gaussian 03 [ 23 ] FeO + Table 1 Theoretica l and exper im en ta l da te for test reaction s Reaction H / ( kj mol - 1 ) Calcd. Exp t. N 2 O + CO N 2 + CO [ 5 ] N /2O 2 N 2 O [ 5 ] N 2 +O ( 3 P) N 2 O [ 21 ] CO +O ( 3 P) CO [ 21 ] Fe + ( 6 D ) +O ( 3 P) FeO + ( 6 + ) [ 14 ] FeO + ( 6 + ) +O ( 3 P) FeO a, < [ 15 ] b a. Peroxo species: Fe ( O 2 ) + ( 6 A 1 ) ; b. dioxo species: OFeO + ( 6 A 1 ). FeO +, [ 24 ] [ 25 ] FeO +. Table 2 O ptim ized geom etr ies, tota l energ ies( corrected w ith ZPE), electron ic conf igura tion s and NBO charges State E / ( kj mol - 1 ) Electronic configuration R Fe O /nm FeO +, 6 +., Q Fe NBO Q O 4 2 ( 6 + ) kj /mol. FeO +, 1 Fe + ( 6 D ) O ( 3 P). 1, FeO + 1, 2 1, , 5 5, Fe O 215., 3 g - O O 6 + FeO +,,. 4 2 FeO + 3,, Fe O nm. NBO,, Fe, 6 + FeO +, Fe O, Fe( O 2 ) + O FeO + F ig. 1 Fron tier m olecular orb ita ls for linear FeO + B3LYP / G ( 2d ) / /B3LYP /6231G ( d ), Fe (O 2 ) +

3 No. 12 : FeO + ( 6 + ) CO N 2 O 2367 OFeO +, Fe O O +. FeO Table 3 O ptim ized geom etr ies, tota l energ ies( corrected w ith ZPE), electron ic conf igura tion s and NBO charges Structure State E / ( kj mol - 1 ) Electronic configuration R Fe O /nm OFeO Fe (O 2 ) + 6 A b 1 1 4a 1 1 5a 1 1 2a 2 1 3b A a 1 1 2b 1 1 3b B b OFeO + 6 A b 2 1 4a 1 1 2b 1 1 5a 1 1 2a B b 1 1 5a 1 1 2a B b , Fe (O 2 ) + OFeO +, 6 A 1,., 9313 kj /mol, CASSCF [ 15 ] ( 134 kj /mol). Schwarz [ 15 ] Fe + O 2 ( < 134 kj / mol). 6 A 1 Fe (O 2 ) + OFeO + Fe + ( 6 D ) O 2 ( 3 - g ), kj / mol, 3011 kj /mol,. 2 6 A 1 Fe (O 2 ) + OFeO +. 2, OFeO +, 6 A Fe 3d ( 4a 1, 2b 1, 5a 1 2a 2 ), (3b 2 ), Fe,,., 4 B 2 2 B 1, Fe 3 d, Fe. Fe O, 6 A 1 Fe O 4 B 2 2 B 1 ( 3), Fe O,. Fe (O 2 ) +, 6 A 1 4 A 2 2 B 1, Fe. 3, Q Fe NBO Schem e 2 Resonance structures of O FeO + F ig. 2 O rb ita l correla tion schem e between O FeO + and Fe( O 2 ) +, OFeO + Fe (O 2 ) +, Fe ( ), ( ). 2, OFeO + ( 6 A 1 ) Fe (O 2 ) + ( 6 A 1 ),. Schwarz [ 15 ] CASPT2D, 4610 kj /mol ; Bell [ 18 ] DFT, ZSM25, 2716 kj /mol., OFeO + Q O ( 6 A 1 ) Fe (O 2 ) + ( 6 A 1 ) 3917 kj /mol, OFeO = 6412, OFeO + ( 6 A 1 ) 9017 Fe (O 2 ) + ( 6 A 1 ) Fe( O 2 ) + O FeO + 1, FeO + /FeO + 2 [ ( 1 ) ], FeO +. N 2 O CO 2,,, (4) (5) [ (4) ]: N 2 O + FeO + N 2 + FeO + 2 (4) CO 2 + FeO + CO + FeO + 2 (5)

4 2368 Vol. 29 FeO + FeO + 2, CO N 2 O. N 2 O O N FeO +, Im1 Im2 ( 3), kj /mol. N - 3, Fe. F ig. 3 B3LY P /6231G( d) optim ized in term ed ia te structures in the N 2 O + CO reaction over FeO + ( 6 + ) Bond lengths in nm, bond angles in degree. 4 N 2 O FeO +., O N 2 O TS1 TS2 O Fe OFeO +, TS3 Fe (O 2 ) +. N N 2 O TS4., N 2 O FeO +, ( TS kj /mol, TS kj /mol) ( TS kj /mol, TS kj /mol)., FeO + N 2 O O, O O, O O, TS3 TS4 ;, Fe O, TS1 TS2. F ig. 4 B3LY P /6231G( d) optim ized tran sition sta te structures in the N 2 O + FeO + reaction to form O FeO + and Fe( O 2 ) + Bond lengths in nm, bond angles in degree. Barrier heights( E in kj /mol) are with respect to the reactants in their ground states. 4, TS1 TS4 N 2 O. NBO, N 2 O ( a. u. ), Fe 3d N 2 O, N O, Stirling [ 26 ] V N 2 O. Toscano [ 10 ] Fe + ( 6 D ) N 2 O, 2212 kj / mol, FeO + ( TS1) 2515 kj /mol. :, Fe + O OFe + O (33315 vs kj /mol), ;, Fe +, FeO +, 3d, N O., L FeO +, (L) FeO + N O. CO 2 O FeO + ( Im3, 3), kj /mol, N 2 O O., CO 2 FeO + 5, 5., TS5 TS6

5 No. 12 : FeO + ( 6 + ) CO N 2 O 2369 OFeO +, TS7 TS9 Fe (O 2 ) +. (5) (4),, CO 2 O FeO + N 2 O.,., ( TS5 TS9), C O nm; ( TS1 TS4) N O nm. 5, CO 2 FeO +, TS7 TS6 112 kj /mol, N 2 O FeO +. ( 4) ( 5), N 2 O CO 2 FeO +, ( TS5 vs. TS1), OFeO +. F ig. 5 B3LY P /6231G( d) optim ized tran sition sta te structures in the CO 2 + FeO + reaction to form O FeO + and Fe( O 2 ) + Bond lengths in nm, bond angles in degree. Barrier heights( E in kj /mol) are with respect to the reactants in their ground states., OFeO + ; Fe (O 2 ) + Table 4 Rela tive energ ies and barr ier he ights for the L type tran sforma tion of d ioxo to peroxo w ith d ifferen t L types H 0 / ( kj mol - 1 ) OFeO + L Fe (O 2 ) + L ts N CO OC , FeO +, (4), TS2, (5), TS5,.,,,,.,. 6 (N 2 O + CO N 2 + CO 2 )., FeO +, spec ies OFeO kj /mol, OFeO +., 4 FeO + 2 L,. 4, L, 4 7 kj /mol, 3917 kj /mol 34 kj /mol., ( 6 + ) CO N 2 O, 6. 6 F ig. 6 Energy( kj /m ol) prof ile for the m ost fea sible reaction pa thway in the N 2 O reduction by CO using FeO + ( 6 + ) a s a ca ta lyst The dotted line rep resents the uncatalyzed direct O2transfer process.

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