1. Wei Lin, Anan Wu, Zin Lu, Daniel A. Obenchain, Stewart E. Novick
The Influence of Fluorination on the Structure of the Trifluoroacetonitrile Water Complex
Wei Lin, Anan Wu, Zin Lu,
Daniel A. Obenchain, Stewart E. Novick

2. Ar-CH3CN
In the Ar-CH3CN complex, an asymmetric top structure was observed
First observed by Ford et. ala
Additional measurements made in a recent work of Lovas and Sobhandadrib
aFord, R.S; Suenram, R. D.; Fraser, G. T.; Lovas, F. J. and Leopold, K. R. J. Chem. Phys. 94 (1991) 5306.
bF. J. Lovas and J. Sobhanadri, J. Mol. Spectrosc., (2015) 307, 59

3. Ar-CF3CN
In the Ar-CF3CN complex, an asymmetric top structure was observed
First reported by Lin and Novicka
Additional measurements made in this work
aW. Lin and S. E. Novick, J. Mol. Spectrosc., (2007) 243, 32.

4. Recent Work on Similar Complexes
CH3CN-H2O was recently published last January by Lovas and Sobhanadri
J. Mol. Spectrosc (2015) 59-64
In addition to the water structure, additional transitions and isotopes were measured for the Ar-CH3CN complex

5. CH3CN-H2O Spectrum presented as an effective symmetric top
Also observed the two tunneling states from the H2O exchange.

6. Predicted Geometries

7. Predicted Geometries Conf-1 Conf-2 Conf-3 E(kcal/mol) 0.00 0.32 2.13
0.61
1.68
A (MHz)
B (MHz)
826.68
C (MHz)
824.83
µa(Debye)
1.39
2.93
-3.66
µb(Debye)
1.27
-1.66
0.47
µc(Debye)

8. Experimental Balle Flygare type FTMW spectrometer
1% CF3CN in 0.5 atm Ar
Bubbled through deionized water
94 hyperfine transitions measured
Also measured new transitions for Ar-CF3CN
16 transitions, with 68 hyperfine transitions

9. Experimental
The transition of the B state of the CF3CN-H2O complex.

10. Parameters Determined in Fit
A state
B state
A /MHz
(48)
(43)
B /MHz
(15)
(14)
C /MHz
(18)
(17)
J /kHz
2.743(32)
2.709(29)
JK /kHz
-3.004(21)
-2.831(19)
K /kHz
4.979(61)
4.680(55)
J /kHz
0.7668(34)
0.7732(32)
K /kHz
0.316(47)
0.407(44)
χaa /MHz
0.263(3)
0.2737(25)
χbb - χcc /MHz
(44)
(40) N 49 45
/kHz
2.3
1.9

11. Predicted Geometries Conf-1 Conf-2 Conf-3 Experimental E(kcal/mol)
0.00
0.32
2.13
E0(kcal/mol)
0.61
1.68
A (MHz)
(48)
B (MHz)
826.68
(15)
C (MHz)
824.83
(18)
µa(Debye)
1.39
2.93
-3.66
µb(Debye)
1.27
-1.66
0.47
µc(Debye)

12. Orientation of the Water Molecule

13. Orientation of the Water Molecule
2 step for each scan coordinate in the 2D potential energy surface

14. Orientation of the Water Molecule
Minimum energy value obtained from the 2D scan
=64 
=0 
=90 

15. CF3CN-H2O & CH3CN-H2O Dipole-dipole interactions
CF3CN =  D
CH3CN =  D

16. Updated Ar-CF3CN Fits Lin et ala This Work A /MHz 3053.0903(2)
(2)
B /MHz
(2)
(9)
C /MHz
(1)
(9)
ΔJ /kHz
2.687(1)
2.6889(6)
ΔJK /kHz
15.904(8)
15.928(4)
ΔK /kHz
-12.38(2)
-12.45(2)
J /kHz
0.4258(8)
0.4260(2)
K /kHz
7.05(5)
6.93(3)
Χaa /MHz
1.746(1)
1.747(1)
χbb- χcc /MHz
-6.426(2)
-6.425(3) N
133
201
 /kHz 2
aW. Lin and S. E. Novick, J. Mol. Spectrosc., (2007) 243, 32.

17. Conclusions
Hydrogen bonding is not the primary interaction in the H2O CF3CN system
Further examination of these types of systems is suggested
Water complex with CH3F
RB10
We also have updated rotational constants for Ar-CF3CN

18. Acknowledgements Novick, Pringle and Cooke Group
NSF Grant # CNS