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New LHCb Collaboration results on pentaquarks with hidden charm 1 are discussed. These results fit nicely in the hadrocharmonium pentaquark scenario.[Formula: see text] In the new data the old LHCb pentaquark [Formula: see text] splits into two states [Formula: see text] and [Formula: see text]. We interpret these two almost degenerated hadrocharmonium states with [Formula: see text] and [Formula: see text], as a result of hyperfine splitting between hadrocharmonium states predicted in Ref. 2. It arises due to QCD multipole interaction between color-singlet hadrocharmonium constituents. We improve the theoretical estimate of hyperfine splitting[Formula: see text] that is compatible with the experimental data. The new [Formula: see text] state finds a natural explanation as a bound state of [Formula: see text] and a nucleon, with [Formula: see text], [Formula: see text] and binding energy 42 MeV. As a bound state of a spin-[Formula: see text] meson and a nucleon, hadrocharmonium pentaquark [Formula: see text] does not experience hyperfine splitting. We find a series of hadrocharmonium states in the vicinity of the wide [Formula: see text] pentaquark that can explain its apparently large decay width. We compare the hadrocharmonium and molecular pentaquark scenarios and discuss their relative advantages and drawbacks.
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Weakly conjugated bacteriochlorin-bacteriochlorin dyad: Synthesis and photophysical properties
Dyads containing two near-infrared absorbing and emitting bacteriochlorins with distinct spectral properties have been prepared and characterized by absorption, emission, and transient-absorption spectroscopies. The dyads exhibit ultrafast ([Formula: see text]3 ps) energy transfer from the bacteriochlorin with the higher-energy S 1 state to the bacteriochlorin emitting at the longer wavelength. The dyads exhibit strong fluorescence and relatively long excited state lifetimes ([Formula: see text]4 ns) in both non-polar and polar solvents, which indicates negligible photoinduced electron transfer between the two bacteriochlorins in the dyads. These dyads are thus attractive for the development of light-harvesting arrays and fluorophores for in vivo bioimaging.
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- Award ID(s):
- 1955318
- PAR ID:
- 10280852
- Date Published:
- Journal Name:
- Journal of Porphyrins and Phthalocyanines
- ISSN:
- 1088-4246
- Page Range / eLocation ID:
- A to J
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1142/S1088424621500711
