Supplementary material for Ash et al. (2000) Proc. Natl. Acad. Sci. USA 97 (19), 10371-10376.

Table 3.

Constants for peptide anisotropic shielding models

Model

A, (qy)

B, (qx)

C, (qz)

Group

Origin (x,z)*

Ösapay & Case (6)

-

13.1

--

--

OCN

-

0.62, - 0.91

Herranz et al. (7)

-

27.4

--

--

OCN

-

0.37, - 1.07

Herranz et al. (7)

--

--

9.24

CO

0.00, - 0.37

Williamson & Asakura (8)

-

13.0

-

4.0

--

CO

0.00, - 0.14

Williamson & Asakura (8)

-

11.0

1.4

--

CN

-

0.55, - 1.60

*Measured from the O atom, assuming bond lengths C=O of 1.24 Å, C-N of 1.325 Å, and OCN angle of 123.5o [Dickerson & Geis (11)].