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True molecular conformation and structure determination of remarkable polycyclic aromatic hydrocarbons
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ECM33 BOOK OF ABSTRACTS
279
MS39 Crystallography at the nanoscale
MS39-03
True molecular conformation and structure determination of remarkable polycyclic aromatic hydrocarbons
I. Andrusenko 1, E. Mugnaioli 2, M. Gemmi 1, W. Schmidt 3
1Istituto Italiano di Tecnologia, Center for Materials Interfaces, Electron Crystallography - Pontedera (Italy),
2Università di Pisa, Dipartimento di Scienze della Terra - Pisa (Italy), 3PAH Research - Igling-Holzhausen
(Germany)
Abstract
The true molecular conformation and the crystal structure of four large (30 – 46 C atoms) polycyclic aromatic
hydrocarbons (PAHs)1,2 were determined by direct methods from 3D electron diffraction (3D ED)3 data, a result
that could not be achieved by single crystal X-ray diffraction (XRD) due to limited crystal size and the thin leaflet
morphology of the samples. Additionally, three of such compounds were isolated as by-products in the synthesis
of similar materials and, therefore, were available only in very limited amount.
The main strength of 3D ED is the ability to perform single crystal diffraction on sub-micrometric areas. Therefore,
this technique can be used for structure determination when crystal size is the limiting factor for single crystal
XRD. Remarkably, this analytical protocol can be performed even on extremely small sample batches, which
cannot be conveniently prepared for conventional powder XRD.
Moreover, the molecular conformation of two compounds could not be determined via classical spectroscopic
methods due to the large size of the molecules and the occurrence of multiple and reciprocally connected
aromatic rings. On the other hand, 3D ED data provided not only ab-initio structure solution, but also the
unbiased determination of the internal molecular conformation. It is noteworthy that ab-initio crystal structure
determination does not require information about the molecular conformation, but only a rough estimation of the
atomic content of the unit cell.
The other two compounds were synthesised more than 50 years ago, but have hitherto remained structurally
unsolved. All molecules have a considerable interest due to their optoelectronic properties, which led to the
creation of a number of functionalised materials based on PAH backbones. Detailed synthetic routes,
spectroscopic analyses and promising properties are also discussed.
References
1. Hall, C. L., Andrusenko, I., Potticary, J., Gao, S., Liu, X., Schmidt, W., Marom, N., Mugnaioli, E., Gemmi, M.
& Hall, S. R. (2021) 3D Electron Diffraction Structure Determination of Terrylene, a Promising Candidate for
Intermolecular Singlet Fission. ChemPhysChem 22(15), 1631-1637.
2. Andrusenko, I., Hall, C. L., Mugnaioli, E., Potticary, J., Schmidt, W., Gao, S., Marom, N., Hall, S. R. & Gemmi,
M. (2022) True Molecular Conformation and Structure Determination by 3D Electron Diffraction of PAH By-
Products Potentially Useful for Electronic Applications, in preparation.
3. Gemmi, M., Mugnaioli, E., Gorelik, T. E., Kolb, U., Palatinus, L., Boullay, P., Hovmöller, S. & Abrahams, J. P.
(2019) 3D Electron Diffraction: The Nanoctystallography Revolution. ACS Cent. Sci. 5, 1315-1329
Nebria molendai HUBER & SCHMIDT 2007
No full text<i>Nebria molendai</i> HUBER & SCHMIDT, 2007 <p>Holotype ♂: Nepal, Rolwaling valley, Na to Omai Tsho lake, 4100–4500 m, 22.5.2000, leg. Schmidt (NMBE).</p> <p>Paratypes: 32 specimens same data as holotype (NMBE, cSCHM).</p>Published as part of <i>Huber, Charles & Schmidt, Joachim, 2017, Notes on the Nebria subgenus Epinebriola K. DANIEL, 1904 with the description of Barbonebriola subgen. nov. and 13 new species from the Himalaya-Tibet orogen (Coleoptera, Carabidae, Nebriini), pp. 1-85 in Contributions to Natural History 36</i> on page 7, DOI: 10.5169/seals-787049, <a href="http://zenodo.org/record/6285683">http://zenodo.org/record/6285683</a>
Chydaeus similis Kataev & Schmidt 2002
No full textChydaeus similis Kataev & Schmidt, 2002 Chydaeus similis Kataev & Schmidt, 2002: 400 Material examined. China. SHAANXI: 1 ♀, S Shaanxi, Qinling Shan, pass on road Zhouzhi-Foping, 105 km SW Xi'an, N slope, 1990 m, 33 ° 44 'N 107 ° 59 'E, small creek valley / mix. deciduous forest / bamboo / small meadows, 2–4.VII. 2001, D. Wrase leg. (cWR). CHONGQING: 1 ♂, 1 ♀, Dabashan Mt. R., NE Heyu Vill., 31 ° 55 ' 17 "N 109 °04' 17 "E – 31 ° 55 ' 16 "N 109 °03' 56 "E, 2115 – 1925 m, 16.V. 2010, I. Belousov, I. Kabak, A. Korolev leg. (cIB&IK, ZIN). Remarks. First record from the Chinese provinces Shaanxi and Chongqing. Previously this species was known from Sichuan and Yunnan (Kataev & Schmidt 2002; Kataev et al. 2012).Published as part of Kataev, Boris M., Wrase, David W. & Schmidt, Joachim, 2014, New species of the genus Chydaeus from China, Nepal, Myanmar, and Thailand, with remarks on species previously described (Coleoptera: Carabidae: Harpalini), pp. 1-28 in Zootaxa 3765 (1) on pages 6-7, DOI: 10.11646/zootaxa.3765.1.1, http://zenodo.org/record/28555
On an Eigendeformation Approach to Brittle Fracture
No full textThe paper presents a numerical implementation of a novel approximation scheme for Griffith’s theory of brittle fracture recently proposed in Schmidt et al. (2009). The total potential energy of a brittle body (including bulk and surface terms) is variationally approximated by a family of functionals, depending on a small penalty parameter ". The (two-field) approximating functionals have as arguments the displacement field u and an eigendeformation field. The latter describes the regions of the body under high strains, where fracture will occur. Gamma-convergence of such a family of functionals to Griffith’s energy has been proved in Schmidt et al. (2009). Here we investigate numerical examples for the quasi-static crack propagation in mixed modes I-II and I-III, through finite element approximation, illustrating the main computational features of the eigenfracture approach
Orthogonal least squares methods and their application to non-linear system identification
No full textIdentification algorithms based on the well-known linear least squares methods ofgaussian elimination, Cholesky decomposition, classical Gram-Schmidt, modifiedGram-Schmidt, Householder transformation, Givens method, and singular valuedecomposition are reviewed. The classical Gram-Schmidt, modified Gram-Schmidt,and Householder transformation algorithms are then extended to combinestructure determination, or which terms to include in the model, and parameterestimation in a very simple and efficient manner for a class of multivariablediscrete-time non-linear stochastic systems which are linear in the parameters
Mayo General Hospital Postcard, front
No full textOn front: "View of Mayo General Hospital, from Entrance, Galesburg, Ill. -- From Lottie Schmidt" Found on page 14
Acutogordius koljai Schmidt-Rhaesa & Karraker, 2017, n. sp.
No full text<i>Acutogordius koljai</i> n. sp. <p>(Figure 5)</p> <p> <b>Holotype.</b> One male from type locality, deposited in the Zoological Museum Hamburg, accession number V13404. <b>Etymology.</b> The species name “ <i>koljai</i> ” is chosen after the youngest son of the senior author, Kolja Tore.</p> <p> <b>Type locality.</b> Malaysia, Sabah, Mt. Kinabalu, Liwagu stream (UTM Zone 50Q, 664160N/44913E), elevation 1515 m; collected by N.E. Karraker on June 20, 2010 (paratype) and July 13, 2010 (holotype).</p> <p> <b>Paratype.</b> One male from type locality, deposited in the Zoological Museum Hamburg, accession number V13405.</p> <p> <b>Description</b>. The holotype is 170 mm long and measures 1.0 mm in width. The paratype is 150 mm long and 0.9 mm in width. Both specimens are light brown, with a dark collar present.</p> <p>The body cuticle is smooth. At the posterior end, the tail lobes strongly taper (Fig. 5 A–C). The postcloacal crescent is semicircular (holotype, Fig. 5 D) to slightly parabolic (paratype, Fig. 5 E). The measurements differ in both specimens. The holotype has a thicker (60 µm posterior of the cloacal opening) and narrower (200 µm distance between both tips) crescent than the paratype (40 µm thick and 240 µm broad). The postcloacal crescent is almost immediately posterior of the cloacal opening (Fig. 5 D, E). Characteristic for the species is a curved line that extends from the posterior tips of the crescent in posterior direction and towards the inner face of the tail lobes (Fig. 5 D, E). It borders a clearly separated region posterior of the postcloacal crescent. The cuticle is structured in this region into roundish to polygonal areas resembling areoles (Fig. 5 D, E). Scattered spines are found on the lateral sides of the tail lobes.</p> <p> <b>Remarks</b>: The genus <i>Acutogordius</i> includes so far 10 described species, all from southern, Gondwana continents (Schmidt-Rhaesa & Geraci 2006, Schmidt-Rhaesa & Schwarz 2016). Characteristic for the genus is that the tail lobes taper distinctly towards a more or less pointed posterior tip. Recent SEM investigations (Schmidt- Rhaesa & Geraci 2006, Schmidt-Rhaesa & Schwarz 2016, Schmidt-Rhaesa & Lalramliana 2016) have discovered fine cuticular characters such as bristles and spines on the body cuticle and in the posterior end, which were probably overlooked in earlier descriptions. A region as described as above from posterior of the postcloacal crescent has been described from no species before and is, given its occurrence in two specimens, assumed to be a characteristic feature of this new species. Additionally, the cloacal opening appears to be in none of the previously described species so close to the postcloacal crescent as in the new species.</p> <p> The species <i>Acutogordius doriae</i> (Camerano, 1890) Heinze, 1952 is the only species reported from Malaysia (Camerano 1899) and therefore from the same region as <i>A. koljai</i>. Both species correspond in having a narrow postcloacal crescent, but differ in several other characters. <i>Acutogordius doriae</i> does not have the curved line and the spines present in the posterior end of <i>A. koljai</i>. Additionally, the tail lobes appear to be stronger pointed in <i>A. doriae</i> as compared to <i>A. koljai</i> (see Camerano 1890, Schmidt-Rhaesa & Geraci 2006).</p>Published as part of <i>Schmidt-Rhaesa, Andreas & Karraker, Nancy E., 2017, Nematomorpha from Hong Kong and description of a new species from Malaysia, pp. 395-405 in Zootaxa 4238 (3)</i> on page 403, DOI: 10.11646/zootaxa.4238.3.6, <a href="http://zenodo.org/record/345800">http://zenodo.org/record/345800</a>
Mayo General Hospital Postcard
No full textCaption on page says, "One of hospitals where Lottie Schmidt (nurse) has worked Also Bill Hambley (doctor)." Found on page 14, Scrapbook 1
Characterization of wafer-level thermocompression bonds
No full textThermocompression bonding joins substrates via a bonding layer. In this paper, silicon substrates were bonded using gold thin films. Experimental data on the effects of bonding pressure (30 to 120 MPa), temperature (260 and 300/spl deg/C), and time (2 to 90 min) on the bond toughness, measured using the four-point bend technique, are presented. In general, higher temperature and pressure lead to higher toughness bonds. Considerable variation in toughness was observed across specimens. Possible causes of the nonuniform bond quality were explored using finite element analysis. Simulation results showed that the mask layout contributed to the pressure nonuniformity applied across the wafer. Finally, some process guidelines for successful wafer-level bonding using gold thin films are presented
Leichosila wagneri Schmidt 2009, sp. n.
No full text<i>Leichosila wagneri</i> Schmidt, sp. n. <p>urn:lsid:zoobank.org:act: 98429FDA-3B9D-44BA-8259-6D83D11CFFBB</p> <p>(Figs. 2, 4, 7)</p> <p> <b>Type material.</b> <b>Holotype</b> male – “C[osta]. RICA: Heredia: / 6 km ENE Vara Blanca, / 1950-2050m, 10°11’N / 84 07’W; 15 ii 2002 / David L. Wagner coll”; “INBio-OET- ALAS / transect / 20/L/01/011”; “Project / ALAS / INB0003216237”; “ HOLOTYPE / <i>Leichosila</i> / <i>wagneri</i> / Schmidt” [red label]; “Genitalia / CNC slide # / 14541”; deposited in INBIO.</p> <p> <b>Diagnosis.</b> Distinguished from <i>L</i>. <i>talamanca</i> by the smaller size and darker colouration of <i>L</i>. <i>wagneri</i>, and by the genitalic characters given under the diagnosis for <i>L</i>. <i>talamanca</i>.</p> <p> <b>Description.</b> A detailed description is given above in the genus description. Characters specific to <i>L</i>. <i>wagneri</i> are as follows: Male (female unknown). <b>Forewing</b> <i>–</i> length 13.4 (<i>n</i> = 1); ground colour dark grey. <b>Hindwing</b> <i>–</i> ground colour dark grey, with indistinct, irregular dark grey subterminal spots and medial spot. <b>Male genitalia</b> – Uncus parallelsided basally, then tapering apically, <i>i</i>. <i>e</i>. bottle-shaped in dorsal profile (Fig. 7); vesica with left diverticulum of two ventro-basal diverticula conical and pointed (Fig. 4b).</p> <p> <b>Etymology.</b> This species is named after David L. Wagner, who collected the type specimen, and whose studies continue to vastly improve our knowledge of the larval biology of North American Lepidoptera.</p> <p> <b>Distribution and biology.</b> <i>Leichosila wagneri</i> is known only from the type specimen, collected in high elevation forest (1950-2050 m) on Volcán Barva (Cordillera Central) in mid February.</p>Published as part of <i>Schmidt, Christian, 2009, A new genus and two new species of arctiine tiger moth (Noctuidae, Arctiinae, Arctiini) from Costa Rica, pp. 89-96 in ZooKeys 9 (9)</i> on page 95, DOI: 10.3897/zookeys.9.151, <a href="http://zenodo.org/record/576455">http://zenodo.org/record/576455</a>
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