Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “single molecule”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 955 records · Page 53
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Facile Fabrication of Self‐Assembly Functionalized Polythiophene Hole Transporting Layer for High Performance Perovskite Solar Cells

Abstract Crystallinity and crystal orientation have a predominant impact on a materials’ semiconducting properties, thus it is essential to manipulate the microstructure arrangements for desired semiconducting device performance. Here, ultra‐uniform hole‐transporting material (HTM) by self‐assembling COOH‐functionalized P3HT (P3HT‐COOH) is fabricated, on which near single crystal quality perovskite thin film can be grown. In particular, the self‐assembly approach facilitates the P3HT‐COOH molecules to form an ordered and homogeneous monolayer on top of the indium tin oxide (ITO) electrode facilitate the perovskite crystalline film growth with high quality and preferred orientations. After detailed spectroscopy and device characterizations, it is found that the carboxylic acid anchoring groups can down‐shift the work function and passivate the ITO surface, retarding the interface carrier recombination. As a result, the device made with the self‐assembled HTM show high open‐circuit voltage over 1.10 V and extend the lifetime over 4,300 h when storing at 30% relative humidity. Moreover, the cell works efficiently under much reduced light power, making it useful as power source under dim‐light conditions. The demonstration suggests a new facile way of fabricating monolayer HTM for high efficiency perovskite devices, as well as the interconnecting layer needed for tandem cell.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2025

Visualizing and analyzing 3D biomolecular structures using Mol* at RCSB.org: Influenza A H5N1 virus proteome case study

The easiest and often most useful way to work with experimentally determined or computationally predicted structures of biomolecules is by viewing their three-dimensional (3D) shapes using a molecular visualization tool. Mol* was collaboratively developed by RCSB Protein Data Bank (RCSB PDB, RCSB.org) and Protein Data Bank in Europe (PDBe, PDBe.org) as an open-source, web-based, 3D visualization software suite for examination and analyses of biostructures. It is capable of displaying atomic coordinates and related experimental data of biomolecular structures together with a variety of annotations, facilitating basic and applied research, training, education, and information dissemination. Across RCSB.org, the RCSB PDB research-focused web portal, Mol* has been implemented to support single-mouse-click atomic-level visualization of biomolecules (e.g., proteins, nucleic acids, carbohydrates) with bound cofactors, small-molecule ligands, ions, water molecules, or other macromolecules. RCSB.org Mol* can seamlessly display 3D structures from various sources, allowing structure interrogation, superimposition, and comparison. Using influenza A H5N1 virus as a topical case study of an important pathogen, we exemplify how Mol* has been embedded within various RCSB.org tools—allowing users to view polymer sequence and structure-based annotations integrated from trusted bioinformatics data resources, assess patterns and trends in groups of structures, and view structures of any size and compositional complexity. In addition to being linked to every experimentally determined biostructure and Computed Structure Model made available at RCSB.org, Standalone Mol* is freely available for visualizing any atomic-level or multi-scale biostructure at rcsb.org/3d-view.

3D biostructure↗
DOE OSTI2020

Connected three-body terms in single-reference unitary many-body theories: Iterative and perturbative approximations

This work introduces various approaches to include connected three-body terms in unitary many-body theories, focusing on the driven similarity renormalization group (DSRG). Starting from the least approximate method—the linearized DSRG truncated to one-, two-, and three-body operators [LDSRG(3)]—we develop several approximate LDSRG(3) models with reduced computational cost. Through a perturbative analysis, we motivate a family of iterative LDSRG(3)-n and -n' (n = 1, 2, 3, 4) methods that contain a subset of the LDSRG(3) diagrams. Among these variants, the LDSRG(3)-2 scheme has the same computational complexity of coupled cluster theory with singles, doubles, and triples (CCSDT), but it outperforms CCSDT in the accuracy of the predicted correlation energies. We also propose and implement two perturbative triples corrections based on the linearized DSRG truncated to one- and two-body operators augmented with recursive semi-quadratic commutators [qDSRG(2)]. Overall, the resulting qDSRG(2)+(T) approach matches the accuracy of the “gold-standard” coupled cluster theory with singles, doubles, and perturbative triples model on the energetics of twenty-eight closed-shell atoms and small molecules.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Benchmarking third-order cluster perturbation theory for electronically excited states

In this study, we investigate the reliability of cluster perturbation (CP) theory applied to the calculation of electronically excited states through a comprehensive benchmark. In CP theory, perturbative corrections are added to the properties of a parent excitation space, which converge toward the properties of a target excitation space. For the CPS(D-n) model, perturbative corrections through order n are added to the coupled cluster singles (CCS) excitation energies to target the coupled cluster singles and doubles (CCSD) excitation energies. Through a comparative analysis of excitation energy calculations across a diverse set of molecules and wavefunction methods, we present a comprehensive evaluation of the accuracy of the third-order CPS(D) model, CPS(D-3), in calculating excitation energies. Further, our findings demonstrate that CPS(D-3) is a reliable alternative to established methods, particularly CCSD, while systematically overestimating the excitation energies compared to high-level coupled cluster methods such as CC3. These results highlight the strengths and limitations of CPS(D-3), as well as the promising directions for its future development.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Step-stool conformation of a cyclic Schiff base derived from ethylenediamine and heptane-2,4,6-trione: evidence for partial hydrolysis in metal coordination

A Schiff base derived from ethylenediamine and heptane-2,4,6-trione, namely, 5,9,14,18-tetramethyl-1,4,10,13-tetraazacyclooctadeca-5,8,14,17-tetraene-7,16- dione (C 18 H 28 N 4 O 2 ), abbreviated H 4 daaden, was prepared and characterized for the first time by single-crystal X-ray diffraction. The atoms of the Schiff base occupy two different planes and thus the molecule is essentially nonplanar. An axis running through the C–C atoms of the ethylenediamine groups separate the two planes and these two planes are connected by bridging ethylene groups showing an angle of 117.34 (8)°. As a result, the side view of the molecule shows a ‘step-stool’ conformation. The nonplanar nature of the Schiff base plays an important role in metal coordination, which leads to partial hydrolysis of the ring structure

crystal structure↗
DOE OSTI2020

Materials Data on SbIrC2(OF3)2 by Materials Project

Ir2F(CO)4Sb2F11 crystallizes in the tetragonal P-4n2 space group. The structure is zero-dimensional and consists of sixteen formaldehyde molecules, four Ir2F clusters, and four Sb2F11 clusters. In each Ir2F cluster, Ir5+ is bonded in a distorted single-bond geometry to one F1- atom. The Ir–F bond length is 2.09 Å. F1- is bonded in a water-like geometry to two equivalent Ir5+ atoms. In each Sb2F11 cluster, Sb3- is bonded to six F1- atoms to form corner-sharing SbF6 octahedra. The corner-sharing octahedral tilt angles are 34°. There are a spread of Sb–F bond distances ranging from 1.89–2.09 Å. There are six inequivalent F1- sites. In the first F1- site, F1- is bonded in a bent 150 degrees geometry to two equivalent Sb3- atoms. In the second F1- site, F1- is bonded in a single-bond geometry to one Sb3- atom. In the third F1- site, F1- is bonded in a single-bond geometry to one Sb3- atom. In the fourth F1- site, F1- is bonded in a distorted single-bond geometry to one Sb3- atom. In the fifth F1- site, F1- is bonded in a single-bond geometry to one Sb3- atom. In the sixth F1- site, F1- is bonded in a single-bond geometry to one Sb3- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on C2IO by Materials Project

C2OI crystallizes in the tetragonal P4_32_12 space group. The structure is zero-dimensional and consists of eight 3,4-diiodo-3-cyclobutene-1,2-dione molecules. there are four inequivalent C sites. In the first C site, C is bonded in a distorted single-bond geometry to one C and one O atom. The C–C bond length is 1.49 Å. The C–O bond length is 1.21 Å. In the second C site, C is bonded in a distorted T-shaped geometry to two C and one I atom. The C–C bond length is 1.39 Å. The C–I bond length is 2.04 Å. In the third C site, C is bonded in a distorted T-shaped geometry to two C and one I atom. The C–C bond length is 1.50 Å. The C–I bond length is 2.05 Å. In the fourth C site, C is bonded in a distorted single-bond geometry to one C and one O atom. The C–O bond length is 1.22 Å. There are two inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one C atom. In the second O site, O is bonded in a single-bond geometry to one C atom. There are two inequivalent I sites. In the first I site, I is bonded in a single-bond geometry to one C atom. In the second I site, I is bonded in a single-bond geometry to one C atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HS3N by Materials Project

NHS3 crystallizes in the orthorhombic Pnma space group. The structure is zero-dimensional and consists of four 1,2,3,5,6,7,4,8-hexathiadiazocane molecules. there are two inequivalent N5+ sites. In the first N5+ site, N5+ is bonded in a distorted single-bond geometry to one H1+ and two equivalent S2- atoms. The N–H bond length is 1.03 Å. Both N–S bond lengths are 1.70 Å. In the second N5+ site, N5+ is bonded in a trigonal planar geometry to one H1+ and two equivalent S2- atoms. The N–H bond length is 1.03 Å. Both N–S bond lengths are 1.68 Å. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N5+ atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N5+ atom. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted single-bond geometry to one N5+ and one S2- atom. The S–S bond length is 2.06 Å. In the second S2- site, S2- is bonded in a water-like geometry to two S2- atoms. The S–S bond length is 2.09 Å. In the third S2- site, S2- is bonded in a distorted single-bond geometry to one N5+ and one S2- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H2O by Materials Project

H2O is Lonsdaleite structured and crystallizes in the hexagonal P6_3cm space group. The structure is zero-dimensional and consists of twelve water molecules. there are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted single-bond geometry to one O2- atom. The H–O bond length is 1.01 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.01 Å. O2- is bonded in a water-like geometry to two H1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H4C5O2 by Materials Project

C5H4O2 is alpha Np-like structured and crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two methyl methacrylate molecules. there are five inequivalent C sites. In the first C site, C is bonded in a distorted single-bond geometry to one C and one H1+ atom. The C–C bond length is 1.40 Å. The C–H bond length is 1.09 Å. In the second C site, C is bonded in a distorted single-bond geometry to one C and one H1+ atom. The C–C bond length is 1.40 Å. The C–H bond length is 1.09 Å. In the third C site, C is bonded in a distorted bent 120 degrees geometry to one C and two O2- atoms. The C–C bond length is 1.49 Å. There is one shorter (1.23 Å) and one longer (1.36 Å) C–O bond length. In the fourth C site, C is bonded in a trigonal planar geometry to three C atoms. In the fifth C site, C is bonded in a distorted trigonal non-coplanar geometry to two H1+ and one O2- atom. Both C–H bond lengths are 1.10 Å. The C–O bond length is 1.45 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one C atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one C atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one C atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one C atom. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to two C atoms. In the second O2- site, O2- is bonded in a single-bond geometry to one C atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on C3N by Materials Project

C3N is BCT5 structured and crystallizes in the orthorhombic P2_12_12_1 space group. The structure is zero-dimensional and consists of four ethanamine, n-methylene- molecules. there are three inequivalent C1+ sites. In the first C1+ site, C1+ is bonded in a distorted single-bond geometry to one C1+ atom. The C–C bond length is 1.35 Å. In the second C1+ site, C1+ is bonded in a single-bond geometry to one C1+ and one N3- atom. The C–N bond length is 1.22 Å. In the third C1+ site, C1+ is bonded in a single-bond geometry to one N3- atom. The C–N bond length is 1.33 Å. N3- is bonded in a bent 150 degrees geometry to two C1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PdRhN5Cl5O by Materials Project

PdCl2PdCl4(RhNCl)2(N2O)2(N2Cl)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of two ac1l8io8 molecules; four hydroxylamine, o-amino- molecules; two palladium(ii) chloride molecules; four N2Cl clusters; and four RhNCl clusters. In each N2Cl cluster, N+0.20+ is bonded in a single-bond geometry to one Cl1- atom. The N–Cl bond length is 1.53 Å. Cl1- is bonded in a distorted bent 120 degrees geometry to two equivalent N+0.20+ atoms. In each RhNCl cluster, Rh4+ is bonded in a 1-coordinate geometry to one N+0.20+ atom. The Rh–N bond length is 1.82 Å. N+0.20+ is bonded in a distorted bent 120 degrees geometry to one Rh4+ and one Cl1- atom. The N–Cl bond length is 1.66 Å. Cl1- is bonded in a single-bond geometry to one N+0.20+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CI(NO)3 by Materials Project

CN2N2CI2(NO3)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of eight ammonia molecules, four cyanamide molecules, and two CI2(NO3)2 clusters. In each CI2(NO3)2 cluster, C4+ is bonded in a single-bond geometry to one N1+ atom. The C–N bond length is 1.25 Å. There are two inequivalent N1+ sites. In the first N1+ site, N1+ is bonded in a bent 120 degrees geometry to one C4+ and one O2- atom. The N–O bond length is 1.31 Å. In the second N1+ site, N1+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.20 Å) and one longer (1.36 Å) N–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one I1- atom. The O–I bond length is 1.80 Å. In the second O2- site, O2- is bonded in a single-bond geometry to one I1- atom. The O–I bond length is 1.81 Å. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one N1+ and one I1- atom. The O–I bond length is 2.17 Å. In the fourth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three I1- atoms. There are a spread of O–I bond distances ranging from 1.95–2.64 Å. In the fifth O2- site, O2- is bonded in a single-bond geometry to one N1+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one N1+ and one I1- atom. The O–I bond length is 2.25 Å. There are two inequivalent I1- sites. In the first I1- site, I1- is bonded in a 3-coordinate geometry to three O2- atoms. In the second I1- site, I1- is bonded in a 4-coordinate geometry to four O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PPtN5ClO6 by Materials Project

PtNPO3N2ON2ClO2 crystallizes in the monoclinic P2_1/m space group. The structure is zero-dimensional and consists of two hydrogen peroxide molecules; two hydroxylamine, o-amino- molecules; two phosphonic acid molecules; two N2Cl clusters; and two PtN clusters. In each N2Cl cluster, N+0.60+ is bonded in a single-bond geometry to one Cl1- atom. The N–Cl bond length is 1.65 Å. Cl1- is bonded in an L-shaped geometry to two equivalent N+0.60+ atoms. In each PtN cluster, Pt5+ is bonded in a distorted single-bond geometry to one N+0.60+ atom. The Pt–N bond length is 1.75 Å. N+0.60+ is bonded in a distorted single-bond geometry to one Pt5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H25C8IN2(OF2)2 by Materials Project

(N(CH3)4)2HF2I(OF)2 is Silicon tetrafluoride-derived structured and crystallizes in the monoclinic C2/m space group. The structure is zero-dimensional and consists of four hydrogen fluoride hydrogen fluoride molecules, eight tetramethylammonium molecules, and four I(OF)2 clusters. In each I(OF)2 cluster, O2- is bonded in a single-bond geometry to one I1- atom. The O–I bond length is 1.80 Å. I1- is bonded in a distorted rectangular see-saw-like geometry to two equivalent O2- and two F1- atoms. Both I–F bond lengths are 2.08 Å. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one I1- atom. In the second F1- site, F1- is bonded in a single-bond geometry to one I1- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on InRe4C14I3O14 by Materials Project

InRe2I(ReI)2(CO)14 crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of fifty-six formaldehyde molecules, four indium molecules, four Re2I clusters, and four ReI clusters. In each Re2I cluster, Re3+ is bonded in a distorted single-bond geometry to one I1- atom. The Re–I bond length is 2.81 Å. I1- is bonded in a 2-coordinate geometry to two equivalent Re3+ atoms. In each ReI cluster, Re3+ is bonded in a 2-coordinate geometry to two equivalent I1- atoms. There are one shorter (2.83 Å) and one longer (2.85 Å) Re–I bond lengths. I1- is bonded in a 4-coordinate geometry to two equivalent Re3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on RePtN5Cl8O by Materials Project

ReCl6PtN3OClN2Cl crystallizes in the orthorhombic Pnma space group. The structure is zero-dimensional and consists of four hexachlororhenium molecules, four N2Cl clusters, and four PtN3OCl clusters. In each N2Cl cluster, N+0.20+ is bonded in a single-bond geometry to one Cl1- atom. The N–Cl bond length is 1.54 Å. Cl1- is bonded in a water-like geometry to two equivalent N+0.20+ atoms. In each PtN3OCl cluster, Pt2+ is bonded in a 4-coordinate geometry to three N+0.20+ and one Cl1- atom. There is one shorter (1.86 Å) and two longer (2.00 Å) Pt–N bond length. The Pt–Cl bond length is 2.41 Å. There are two inequivalent N+0.20+ sites. In the first N+0.20+ site, N+0.20+ is bonded in a single-bond geometry to one Pt2+ atom. In the second N+0.20+ site, N+0.20+ is bonded in a single-bond geometry to one Pt2+ and one O2- atom. The N–O bond length is 1.35 Å. O2- is bonded in a water-like geometry to two equivalent N+0.20+ atoms. Cl1- is bonded in a single-bond geometry to one Pt2+ atom.

36 MATERIALS SCIENCE↗