. Author manuscript; available in PMC: 2018 Feb 1.

Published in final edited form as: J Am Soc Mass Spectrom. 2016 Dec 2;28(2):323–331. doi: 10.1007/s13361-016-1525-7

Table 3.

Comparison of experimentally-measured and trajectory method-calculated gas-phase CCS. As several structures were optimized for the dimers with different initial torsional angles, the dimer results are averages weighted by the Boltzmann factors for T = 298 K with the respective energy of each optimized structure. Experimental errors and theoretical standard deviations are also shown.

Binding mode	Androsterone		Trans-Androsterone

	Theoretical CCS (Å²)	Experimental CCS (Å²)	Theoretical CCS (Å²)	Experimental CCS (Å²)
	Results for Sodiated Monomers:
Na⁺ binding at ketone	186.9 ± 2.1	197.1 ± 0.2	186.2 ± 1.2	196.8 ± 0.2
Na⁺ binding at hydroxyl	180.8 ± 0.9	197.1 ± 0.2	190.2 ± 1.4	196.8 ± 0.2
	Results for Sodiated Dimers:
R=O - - Na⁺ - - O=R′	250.4 ± 1.7	242.6 ± 0.3	245.7 ± 2.1	256.3 ± 0.3
R=O - - Na⁺ - - OH—R′	234.7 ± 2.3		246.0 ± 2.2
R—HO - - Na⁺ - - OH—R′	237.4 ± 3.2		257.4 ± 2.2