Supporting Information

Transcription

1 Supporting Information for Structural Characterization of Two-Dimensional Ternary Inclusion Crystals at the Air-Water Interface David J. Plaut, Stephen M. Martin, Kristian Kjaer, Markus J. Weygand, Meir Lahav, Leslie Leiserowitz, Isabelle Weissbuch,*, and Michael D. Ward*, Information Page S1. Complete GIXD data for all crystalline Langmuir monolayers (A L) 2 S2. Summary of GIXD data for (G)C16BPS:p-chlorohexadecylbiphenyl 14 S3. Calculated and Experimental X-ray Powder Pattern 15 for 4-hexylbiphenyl (C6BP) S4. Unit Cell Index Parameters and Refinement for C6BP 16 S5. GIXD analysis for C16BPS:C16BP-Cl on pure water 17 S6. Atomic force microscopy data for C16BPS:C24 18 Langmuir-Blodgett film (Phase II) 1

2 S1. Complete GIXD data for all crystalline Langmuir monolayers (no background subtracted) A. C16BPS on pure water at A mol = 30 Å 2 /sulfonate (the GIXD pattern was essentially unchanged within the range 25 Å 2 < A mol < 50 Å 2 /sulfonate) 2

3 B. C16BPS on 0.01 M G 2 CO 3 at A mol = 30 Å 2 /sulfonate (the GIXD pattern was essentially unchanged within the range A mol < 42 Å 2 /sulfonate) 3

4 C. C16BPS:C16BP on pure water at A mol = 48 Å 2 /sulfonate (the GIXD pattern was essentially unchanged within the range 48 < A mol < 70 Å 2 /sulfonate) 4

5 D. C16BPS:C16BP on 0.01 M G 2 CO 3 at A mol = 48 Å 2 /sulfonate (the GIXD pattern was essentially unchanged within the range 48 < A mol < 70 Å 2 /sulfonate) 5

6 E. C16BPS:C6BP on pure water at A mol = 40 Å 2 /sulfonate (the GIXD pattern was essentially unchanged at 60 Å 2 /sulfonate) 6

7 F. C16BPS:C6BP on 0.01 M G 2 CO 3 at A mol = 30 Å 2 /sulfonate (the GIXD pattern was essentially unchanged within the range 30 < A mol < 70 Å 2 /sulfonate) 7

8 G. C16BPS:C16BP-Cl on pure water at A mol = 50 Å 2 /sulfonate (the GIXD pattern was essentially unchanged within the range 50 < A mol < 70 Å 2 /sulfonate) 8

9 H. C16BPS:C16BP-Cl on 10-2 M G 2 CO 3 at A mol = 50 Å 2 /sulfonate (the GIXD pattern was essentially unchanged within the range 50 < A mol < 70 Å 2 /sulfonate) 9

10 I. C16BPS:C24 Phase I on pure water at A mol = 50 Å 2 /sulfonate (the GIXD pattern was essentially unchanged within the range 50 < A mol < 70 Å 2 /sulfonate) 10

11 J. C16BPS:C24 Phase I on 10-2 M G 2 CO 3 at A mol = 50 Å 2 /sulfonate (the GIXD pattern was essentially unchanged within the range 50 < A mol < 70 Å 2 /sulfonate) 11

12 K. C16BPS:C24 Phase II on pure water at A mol = 50 Å 2 /sulfonate (the GIXD pattern was essentially unchanged within the range 50 < A mol < 70 Å 2 /sulfonate) 12

13 L. C16BPS:C24 Phase II on 10-2 M G 2 CO 3 at A mol = 50 Å 2 /sulfonate (the GIXD pattern was essentially unchanged within the range 50 < A mol < 70 Å 2 /sulfonate) 13

14 S2. 4 -chloro-4-n-hexadecylbiphenyl intercalate. In order to probe the influence of guest substituents on host-guest interactions and GS monolayer formation, monolayers containing 4 -chloro-4-n-hexadecylbiphenyl (C16BP-Cl) were examined. The introduction of the bulky chloro substituent in the 4-position was expected to result in either (i) intercalation of C16BP-Cl into the (G)C16BPS host with the GS network intact but with the chloro group forcing a vertical offset of the biphenyl and alkane substituents of the host and guest, (ii) immersion of the polar chloro substituent in the aqueous subphase, thereby blocking assembly of the GS network but optimizing the host-guest biphenyl-biphenyl and alkyl-alkyl interactions above the air-water interface, or (iii) the guest inverted so that the chlorobiphenyl moiety protrudes from the upper surface of the host monolayer. The!-A isotherm of C16BPS:C16BP-Cl (Figure S2.a) on pure water exhibited a somewhat smaller A lift-off (ca. 50 Å 2 /sulfonate) and a steeper slope compared with the isotherm obtained over 0.01 M G 2 CO 3. The Bragg peaks for the crystalline monolayer on pure water were indexed to a rectangular unit cell with a = 5.68 Å, b = 8.32 Å, and A cell = 47.3 Å 2. The q z scattering associated with the Bragg peak at q xy = 1.34 A -1 can be deconvoluted into four peaks with maxima at 0.19, 0.43, 0.76 and 0.99 A -1. Taking into account the "Peterson condition" i and the reflection at q xy = 1.51 A -1, q z = 0.55 A -1, a basic subcell would produce only one pair of intensity modulations for q xy =1.34 A -1, either q z = 0.43 A -1, 0.99 A -1 or q z = 0.19 A -1, 0.76 A -1. The observation of four modulations in the q z scattering at q xy = 1.34 A -1 therefore argues the existence of two crystalline phases, one in which the alkyl chains tilt 35 from the normal to the air-water interface in an azimuthal direction 149 from the a-axis and another with a alkyl chain tilt of 30 in an azimuthal direction of 139 (Table 1). The Bragg peaks for C16BPS:C16BP-Cl on 0.01 M G 2 CO 3 were indexed to a slightly smaller rectangular unit cell with a = 5.56 Å, b = 8.11 Å, and A cell = 45.1 Å 2. The alkyl chains tilt 31 from the normal to the air-water interface, in an azimuthal direction 151 from the a-axis. A comparison of the GIXD data and structural parameters for C16BPS:C16BP-Cl monolayers, with and without G in the subphase, and the C16BPS:C16BP monolayer on pure water revealed similar unit cell dimensions, alkyl chain tilt angle, and alkyl tilt direction, indicating essentially identical alkyl chain packing arrangements. Furthermore, the structures of the C16BPS:C16BP-Cl monolayers deduced by refinement of the GIXD data suggested packing arrangements similar to that of the C16BPS:C16BP monolayer on pure water (see Supporting Information). When combined with the Langmuir isotherms, these results suggest that the chloro substituent on the C16BP-Cl guest sterically blocks the G ion from the airwater interface and frustrates the formation of the GS network, which accounts for the similarity of the three monolayers. This preserves the vertical registration of the biphenyl and alkyl groups of C16BPS and C16BP-Cl so that optimal packing of these groups can be achieved. Figure S2. (a)!-a isotherms of C16BPS:C16BP-Cl on pure water (black) and on 0.01 M G 2CO 3 (red). GIXD patterns shown as two-dimensional contour plots of the scattered intensity, I(q xy,q z), measured from C16BPS:C16BP-Cl on (b) pure water, and (c) 0.01 M aqueous G 2CO 3. The angles t and ψ are defined in Figure 6. 14

15 S3. Calculated (red) and experimental (black) X-ray powder pattern for 4-hexylpbiphenyl (C6BP). calculated from single crystal structure: Cu radiation λ = Å, T = 100 K experimental: Siemens D-5005, Cu/Kα 1 = Å, T = 273 K, 2θ = º (shown to 35º), increment = 0.01º, dwell time = 2 sec 15

16 S4. Unit Cell Index and Refinement report for 4-hexylbiphenyl (C6BP) JADE: Cell Refinement Report SCAN: 3.5/36.78/0.04/1(sec), Cu, I(max)=18440 PEAK: 17-pts/Parabolic Filter, Threshold=3.0, Cutoff=0.1%, BG=3/1.0, Peak- Top=Summit NOTE: Intensity = Counts, 2T(0)=0.0( ), Wavelength to Compute d-spacing = Å (Cu/K-alpha1) Cell Type = Monoclinic(Primitive), P21/c (14) (b-unique) Initial Cell = x x <90.0 x x 90.0> Refined Cell = ( ), ( ), ( ) [ (0.2432)] Vol= A^3, Density(c)= (Chemical Formula =(Unknown), Z=0.0) 2-Theta Error Window = 0.3( ), Zero Offset = 0.0( ), Displacement = 0.0( ) ESD of Fit = ( ), Delta 2-Theta = ( ), Delta d = (Å), F(12) = 18.6(15) Least-Square Weighting = None, 2-Theta Range = 3.5/36.78( ), (x) Outlier Rejection at 2.0 sigmas 2T(cor) = 2T(obs) - Zero Offset - Displacement (cal=calculated, obs=observed, cor=corrected) ( h k l) 2T(cal) 2T(cor) 2T(obs) Delta d(cal) d(cor) d(obs) Del-d? ( 2 0 0) ( 3 0 0) ( 4 0 0) ( 6 0 0) ( 4 1 0) ( 2 1 1) ( 3 1 1) ( 1 0-2) ( 2 0 2) ( 5 1 1) ( 8 1 0) ( 3 1-2) ( 3 1 2) ( 8 1 1) ( 5 1 2)

17 S5. (a) GIXD surface plot of the scattered intensity measured from C16BPS:C16BP-Cl on pure water. (b) The q z scattering associated with the Bragg peak at q xy = 1.34 A -1 can be deconvoluted into four peaks with maxima at 0.19, 0.43, 0.76 and 0.99 A -1. Taking into account the "Peterson condition" and the reflection at q xy = 1.51 A -1, q z = 0.55 A -1, a basic subcell would produce only one pair of intensity modulations for q xy =1.34 A -1, either q z = 0.43 A - 1, 0.99 A -1 or q z = 0.19 A -1, 0.76 A -1. (c) Experimental (black dots) and calculated (blue lines) Bragg rod intensity profiles, I(q z ), for as refined for C16BPS:C16BP-Cl with {11} maximum at q xy = 1.34 A -1, q z = 0.43 A -1 and {1-1} maximum at q xy = 1.34 A -1, q z = 0.99 A -1 to equate a molecular tilt of 35 from the normal to the air-water interface in an azimuthal direction 149 from the a-axis. The refined 2-D packing arrangement of C16BPS:C16BP-Cl as viewed down the (d) a- and (e) b-axes, respectively. 17

18 S6. (a) AFM height image performed in tapping mode (force constant 14 N/m, resonant frequency 270 khz, scan rate 2 Hz) of C16BPS:C24 Langmuir-Blodgett (LB) film on mica transferred from a pure water subphase at 32 Å 2 /sulfonate (Phase II). The LB films for AFM measurements were prepared by transfer of the Langmuir monolayers to a mica substrate (Ted Pella Inc.). Only one-half of the mica substrate was coated so that the film thickness could be measured relative to the bare mica surface. (b) Average film thickness of 28.1 Å (calculated from the averages heights between the red and green lines) measured within the rectangle in (a). i Kaganer, V.M.; Peterson, I.R.; Kenn, R.M.; Shih, M.C.; Durbin, M.; Dutta, P. J. Chem. Phys. 1995, 102,