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Title: Headward growth and branching in subterranean channels

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Publication Date:
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
Grant/Contract Number:
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review E
Additional Journal Information:
Journal Volume: 96; Journal Issue: 5; Related Information: CHORUS Timestamp: 2017-11-17 10:08:48; Journal ID: ISSN 2470-0045
American Physical Society
Country of Publication:
United States

Citation Formats

Kudrolli, Arshad, Ionkin, Nikolay, and Panaitescu, Andreea. Headward growth and branching in subterranean channels. United States: N. p., 2017. Web. doi:10.1103/PhysRevE.96.052904.
Kudrolli, Arshad, Ionkin, Nikolay, & Panaitescu, Andreea. Headward growth and branching in subterranean channels. United States. doi:10.1103/PhysRevE.96.052904.
Kudrolli, Arshad, Ionkin, Nikolay, and Panaitescu, Andreea. 2017. "Headward growth and branching in subterranean channels". United States. doi:10.1103/PhysRevE.96.052904.
title = {Headward growth and branching in subterranean channels},
author = {Kudrolli, Arshad and Ionkin, Nikolay and Panaitescu, Andreea},
abstractNote = {},
doi = {10.1103/PhysRevE.96.052904},
journal = {Physical Review E},
number = 5,
volume = 96,
place = {United States},
year = 2017,
month =

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on November 17, 2018
Publisher's Accepted Manuscript

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  • In making defect-free macromolecules, the challenge occurs during chemical synthesis. This challenge is especially pronounced in dendrimer synthesis where exponential growth quickly leads to steric congestion. To overcome this difficulty, proportionate branching in dendrimer growth is proposed. In proportionate branching, both the number and the length of branches increase exponentially but in opposite directions to mimic tree growth. The effectiveness of this strategy is demonstrated through the synthesis of a fluorocarbon dendron containing 243 chemically identical fluorine atoms with a MW of 9082 Da. Monodispersity is confirmed by nuclear magnetic resonance spectroscopy, mass spectrometry, and small-angle X-ray scattering. Moreover, growingmore » different parts proportionately, as nature does, could be a general strategy to achieve defect-free synthesis of macromolecules.« less
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  • We present a generally applicable experimental method for the direct measurement of nascent spin-orbit state distributions of atomic photofragments based on the detection of vacuum ultraviolet (VUV)-excited autoionizing-Rydberg (VUV-EAR) states. The incorporation of this VUV-EAR method in the application of the newly established VUV-VUV laser velocity-map-imaging-photoion (VMI-PI) apparatus has made possible the branching ratio measurement for correlated spin-orbit state resolved product channels, CO(ã{sup 3}Π; v) + O({sup 3}P{sub 0,1,2}) and CO(Χ{sup ~1}Σ{sup +}; v) + O({sup 3}P{sub 0,1,2}), formed by VUV photoexcitation of CO{sub 2} to the 4s(1{sub 0}{sup 1}) Rydberg state at 97,955.7 cm{sup −1}. The total kinetic energy releasemore » (TKER) spectra obtained from the O{sup +} VMI-PI images of O({sup 3}P{sub 0,1,2}) reveal the formation of correlated CO(ã{sup 3}Π; v = 0–2) with well-resolved v = 0–2 vibrational bands. This observation shows that the dissociation of CO{sub 2} to form the spin-allowed CO(ã{sup 3}Π; v = 0–2) + O({sup 3}P{sub 0,1,2}) channel has no potential energy barrier. The TKER spectra for the spin-forbidden CO(Χ{sup ~1}Σ{sup +}; v) + O({sup 3}P{sub 0,1,2}) channel were found to exhibit broad profiles, indicative of the formation of a broad range of rovibrational states of CO(Χ{sup ~1}Σ{sup +})  with significant vibrational populations for v = 18–26. While the VMI-PI images for the CO(ã{sup 3}Π; v = 0–2) + O({sup 3}P{sub 0,1,2}) channel are anisotropic, indicating that the predissociation of CO{sub 2} 4s(1{sub 0}{sup 1}) occurs via a near linear configuration in a time scale shorter than the rotational period, the angular distributions for the CO(Χ{sup ~1}Σ{sup +}; v) + O({sup 3}P{sub 0,1,2}) channel are close to isotropic, revealing a slower predissociation process, which possibly occurs on a triplet surface via an intersystem crossing mechanism.« less
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