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Figure S2. Alternative view of two-fold interpenetrated diamondoid network exhibited by 2.

Colours as in Figure S1. Hydrogen atom, water molecules and DMF molecules are not shown.

3.2 Powder diffraction

The polycrystalline sample 3 was lightly ground in an agate mortar and pestle and filled into 1.0

mm borosilicate glass capillary prior to being mounted and aligned on a Bruker-AXS D8

Advance powder diffractometer, using Cu K

α1

radiation (λ = 1.54056 Å). One dataset (2θ = 3 –

65 º) was collected at room temperature using variable a count time (VCT) [3] scheme (3.00 –

43.00 º = 5 s/step; 43.00 – 65.00 º = 20 s/step) for 0.017 º steps. The diffraction pattern was

indexed using DICVOL91 [4] to a triclinic cell [F(18) = 54.5, M(18) = 24.1] and space group P-1

was assigned from volume considerations [5]. The presence of two, weak peaks at low angle

which were not accounted for by the indexed cell and space group indicate the presence of a

small amount of polycrystalline impurity in the sample. The dataset was background-subtracted

for Pawley refinement [6] and structure solution was performed using the simulated annealing

(SA) global optimization procedure, described previously [7], as implemented in the DASH

computer program [8]. Z-matrices describing the molecular topology of the fragments were

generated within DASH using analogous moieties taken from the CSD [9] and manually

modified using standard bond lengths and angles.

Global optimization of external (rotational for the half-ligand; translational for Zn and both water

oxygens) degrees of freedom against the extracted intensities was carried out with cooling rate set

to 0.01 and all other DASH SA control parameters set to default values. One hundred SA runs

with 2.5×10

SA moves per run were implemented for the structure determination. The SA

structure solution involved the optimisation of four independent fragments in the asymmetric unit

(one Zn

ion, one half-ligand and two water molecules), totalling 17 degrees of freedom. The

position of the half ligand was constrained to rotate around the origin using a dummy atom in the

z-matrix (reducing the external (rotational) degrees of freedom by 3. All degrees of freedom were

assigned random values at the start of the simulated annealing. The best SA solutions had

(profile)/χ

(Pawley) ratio of 4.77 and a chemically reasonable packing arrangement. The solved

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