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The structures of a series of 2:1 cocrystals formed between 4-(dimethylamino)pyridine and each of 1,2,4,5-tetrachloro-3,6-diiodobenzene, 2C7H10N2·C6Cl4I2, 1,2,4,5-tetrabromo-3,6-diiodobenzene, 2C7H10N2·C6Br4I2, 1-bromo-4-iodo-2,3,5,6-tetrafluorobenzene, 2C7H10N2·C6BrF4I, and 1,2-dibromo-4,5-difluoro-3,6-diiodobenzene, 2C7H10N2·C6Br2F2I2, are reported. In all five structures, the core halogen-bonded 2:1 trimolecular units have geometrically similar parameters, with the central halogen-bond donor flanked by two pyridine halogen-bond acceptors twisted with respect to the central halogen-bond donor at angles ranging from 76 to 86°. The I...N halogen-bond separations are all short, ranging from 73.3 to 76.7% of the sum of the van der Waals radii, while the C—I...N bond angles are essentially linear. The Br...N halogen-bond separation in the cocrystal formed with 1-bromo-4-iodo-2,3,5,6-tetrafluorobenzene is 80.4% of the sum of the van der Waals radii. Subtle differences in the crystal packings are attributed to the role of secondary C—H...π and weak π-type interactions with chloro and bromo substituents. The cocrystals 2C7H10N2·C6Cl4I2and 2C7H10N2·C6Br4I2are isomorphous.
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Modeling estimates of agricultural and natural soil nitrous oxide emissions across the contiguous United States: Annual time-series gridded database during 1900-2019
This dataset includes the time-series maps of the model-estimated N2</sub>O emissions, covering the lower U.S. spanning from 1900 to 2019.
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- PAR ID:
- 10336602
- Publisher / Repository:
- figshare
- Date Published:
- Subject(s) / Keyword(s):
- Environmental Science
- Format(s):
- Medium: X Size: 134650813 Bytes
- Size(s):
- 134650813 Bytes
- Sponsoring Org:
- National Science Foundation
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