1. Department of Chemistry, University of Kentucky, Lexington, KY, 40506
Pulsed-Field Ionization Electron Spectroscopy of Copper-Diazine Complexes
XU WANG, JUNG SUP LEE and DONG-SHENG YANG
Department of Chemistry, University of Kentucky, Lexington, KY, 40506

2. Motivations
C4H4N2: important constituents of natural and synthetic compounds; e.g.: DNA, RNA ;
/ binding ability;
Binding effects of mutual N positions.
(a) pyrazine (D2h) 0.00 D
(b) pyrimidine (C2v)
2.33 D
(c) pyridazine (C2v)
4.22 D

3. Schematic Diagram of PFI-ZEKE Apparatus

4. Cu-Pyrazine
ZEKE/He a
0-0 * * *
AIE: 46038(5)
a: 265

5. Cu-Pyrazine
ZEKE/He a b
0-0 * * *
AIE: 46038(5)
a: 265
b: 906

6. Cu-Pyrazine
ZEKE/He a b
0-0 * * *
AIE: 46038(5)
a: 265
b: 906

7. Theoretical Structures of Cu-Pyrazine
1 imaginary frequency
-structure
1.867 Å
E = kJ/mol
2.011 Å
1.909 Å
-structure
Neutral
Ion

8. Cu-Pyrazine AIE: 46038 a: 265 b: 906 b a * * * (a) ZEKE/He
0-0 * * *
(a) ZEKE/He
(b) 1A1-2A1, 80 K

9. Cu-Pyrazine AIE: 46038 10+: 265 8+: 906 * * * (a) ZEKE/He
0-0 * * *
(a) ZEKE/He
(b) 1A1-2A1, 80 K

10. Observed Vibrations Cu-pyrazine stretch, 10+/ 10, a1, 265/190 cm-1
Cu-pyrazine o.p. bend
18+/ 18, b1, 115/74 cm-1
ring i.p. breath
8+, a1, 906 cm-1

11. Cu-Pyrimidine
ZEKE/He * * *
0-0

12. Cu-Pyrimidine
ZEKE/He
AIE: 45332(5) a: 270 a * * *
0-0

13. Cu-Pyrimidine
ZEKE/He
AIE: 45332(5) a: 270; b: 160 a b
0-0

14. Cu-Pyrimidine He
Ar:He = 1:1

15. Theoretical Structures of Cu-Pyrimidine
2.035Å
3.416 Å
E = kJ/mol
E = kJ/mol
2.021 Å
1.908 Å
-structure
Neutral
Ion

16. Cu-Pyrimidine AIE: 45332 a: 270 b: 160 a b * * * (a) ZEKE/He
0-0
(a) ZEKE/He
(b) 1A-2A, 80 K
(c) 1A-2A, 80 K

17. Cu-Pyrimidine AIE: 45332 18+: 270 19+: 160 * * * (a) ZEKE/He
0-0
(a) ZEKE/He
(b) 1A-2A, 80 K
(c) 1A-2A, 80 K

18. Cu-Pyrimidine AIE: 45332 18+: 270 19+: 160 (a) ZEKE/(Ar:He=1:1)
0-0
(a) ZEKE/(Ar:He=1:1)
(b) 1A-2A, 10 K

19. Cu-pyrimidine o.p. bend a
Observed Vibrations
Cu-pyrimidine stretch, 18+/ 18, a, 270/189 cm-1
Cu-pyrimidine i.p. bend
19+/ 19, a, 160/151 cm-1
Cu-pyrimidine o.p. bend a
27+ - 27 = 38 cm-1

20. Cu-Pyridazine
ZEKE/He
AIE: 43054(5) a: b: 131 b a
0-0

21. Cu-Pyridazine
ZEKE/He
AIE: 43054(5) a: b: 131 b a
0-0

22. Cu-Pyridazine
ZEKE/He
AIE: 43054(5) a: b: 131 b a
0-0

23. Theoretical Structures of Cu-Pyridazine
1 imaginary frequency
-structure
1.983 Å
E = kJ/mol
2.000 Å
1.904 Å
-structure
118
108
Neutral
Ion

24. Cu-Pyridazine AIE: 43054 a: 273 b: 131 a b (a) ZEKE/He
0-0
(b) 1A-2A, 80 K

25. Cu-Pyridazine AIE: 43054 18+: 273 19+: 131 (a) ZEKE/He
0-0
(b) 1A-2A, 80 K

26. Cu-Pyridazine AIE: 43054 18+: 273 19+: 131 (a) ZEKE/He
0-0
(b) 1A-2A 80 K

27. Observed Vibrations Cu-pyridazine stretch, 18+/ 18, a, 273/192 cm-1
Cu-pyridazine i.p. bend
19+/ 19, a, 131/123 cm-1
Cu-pyridazine o.p. bend
a, 27+ - 27 = 38 cm-1

28. Summary Cu-pyrazine Cu-pyrimidine Cu-pyridazine -structure AIE, eV
46038(5)
45332(5)
43054(5)
D0 , kJ mol-1
48.5
46.4
56.2
D0+ , kJ mol-1
243.2
249.6
286.6
Cu-N, Å
2.011
2.021
2.000
Cu+-N, Å
1.909
1.908
1.904
Cu+/Cu-L stretch, cm-1
265/190
270/189
273/192
1A1←2A1
1A←2A

29. Thank you!