Results 11 to 20 of about 23,422 (216)
Bis(azuleno)pentalenes with Six Consecutive Odd-Membered Rings. [PDF]
Angew Chem Int Ed EnglA new class of non‐alternant, non‐benzenoid polycyclic hydrocarbons with a unique 7‐5‐5‐5‐5‐7 odd‐membered ring topology has been synthesized. These compounds possess distinct electronic structures that integrate aromatic azulene and antiaromatic pentalene units, resulting in narrow band gaps, near‐infrared absorption, reversible acid‐base ...
Jiang Q +6 more
europepmc +3 more sources
Synthesis, Structures, and Properties of Dehydrobiphenyleno[12]Annulenes: Carbon-Rich Compounds Comprising Two Different Antiaromatic Units. [PDF]
Chem Asian JCarbon‐rich compounds dehydrobiphenyleno[12]annulenes (DBP[12]As) comprising antiaromatic four‐membered rings (4MR) and 12‐membered ring (12MR) were synthesized and characterized. DBP[12]As feature high HOMO energy levels and narrow HOMO‐LUMO gaps. The 4MRs have stronger antiaromatic character than the 12MR in DBP[12]As. Abstract In this work we report
Suzuki K +7 more
europepmc +2 more sources
Electro-mechanically switchable hydrocarbons based on [8]annulenes
Nature Communications, 2022 Pure hydrocarbons with properties that can be switched by external stimuli are interesting for the design and development of new responsive materials. Here, the authors develop an oligomeric [8]annulene-based material that combines topological switching ...
Magdalena Tasić +9 more
doaj +1 more source
Multiple solutions of coupled-cluster equations for PPP model of [10]annulene [PDF]
, 2002 Multiple (real) solutions of the CC equations (corresponding to the CCD, ACP and ACPQ methods) are studied for the PPP model of [10]annulene, C_{10}H_{10}.
Drexler +16 more
core +2 more sources
Complete spectrum of the infinite-$U$ Hubbard ring using group theory [PDF]
, 2014 We present a full analytical solution of the multiconfigurational strongly-correlated mixed-valence problem corresponding to the $N$-Hubbard ring filled with $N-1$ electrons, and infinite on-site repulsion.
Alessandro Soncini +5 more
core +1 more source
Molecules, 2005 Sesqui- and sesterterpenes of ophiobolin and fusicoccin families are important synthetic targets because of complexity of structure and potentially useful physiological activities, including anti-tumor activity.
J. Wicha, M. Michalak, K. Michalak
doaj +1 more source
The Silacyclobutene Ring: An Indicator of Triplet State Baird-Aromaticity
Inorganics, 2017 Baird’s rule tells that the electron counts for aromaticity and antiaromaticity in the first ππ* triplet and singlet excited states (T1 and S1) are opposite to those in the ground state (S0). Our hypothesis is that a silacyclobutene (SCB) ring fused with
Rabia Ayub +2 more
doaj +1 more source
Ximaoornatins A–C, Polyoxygenated Diterpenoids from the Hainan Soft Coral Sinularia ornata
Marine Drugs, 2022 Three complex polyoxygenated diterpenoids possessing uncommon tetradecahydro-2,13:6,9-diepoxybenzo[10]annulene scaffold, namely ximaoornatins A–C (1–3), one new eunicellin-type diterpene, litophynin K (4), and a related known compound, litophynol B (5 ...
Li-Li Sun, Xu-Wen Li, Yue-Wei Guo
doaj +1 more source
Realistic theory of electronic correlations in nanoscopic systems [PDF]
, 2017 Nanostructures with open shell transition metal or molecular constituents host often strong electronic correlations and are highly sensitive to atomistic material details. This tutorial review discusses method developments and applications of theoretical
Barthel, S. +5 more
core +1 more source
The Synthesis of Benzannelated Annulenes. Dibenzo-tetrakisdehydro[18]annulene, and Tribenzo-bisdehydro[14]annulene [PDF]
Bulletin of the Chemical Society of Japan, 1976 Abstract In order to establish the effect of the annelation of benzene rings on [4n+2] annulenes, the syntheses of benzannelated dehydroannulenes were attempted. Dibenzo-tetrakisdehydro[ 18]annulenes (IIa and IIb) were prepared according to the reaction sequence developed in the synthesis of tetramethyltetrakisdehydro[18]annulene (I ...
J\={u}ro Ojima +2 more
openaire +1 more source