2,277 research outputs found
(Z)-Isobutyl 2-benzamido-3-(4-chlorophenyl)acrylate
The title compound, C20H20ClNO3, is a α-amino acid derivative which displays a Z configuration about the C=C double bond. The dihedral angle betwen the aromatic rings is 87.75 (12)°. The molecular conformation is stabilized by an intramolecular C—H⋯N hydrogen bond. In the crystal structure, centrosymmetrically related molecules interact through intermolecular C—H⋯O hydrogen-bond interactions, forming dimers. The dimers are further linked into chains parallel to the a axis by N—H⋯O hydrogen bonds. The methyl groups of the isopropyl group are disordered over two positions with occupancy factors of 0.5
PINE: Universal Deep Embedding for Graph Nodes via Partial Permutation Invariant Set Functions
Graph node embedding aims at learning a vector representation for all nodes
given a graph. It is a central problem in many machine learning tasks (e.g.,
node classification, recommendation, community detection). The key problem in
graph node embedding lies in how to define the dependence to neighbors.
Existing approaches specify (either explicitly or implicitly) certain
dependencies on neighbors, which may lead to loss of subtle but important
structural information within the graph and other dependencies among neighbors.
This intrigues us to ask the question: can we design a model to give the
maximal flexibility of dependencies to each node's neighborhood. In this paper,
we propose a novel graph node embedding (named PINE) via a novel notion of
partial permutation invariant set function, to capture any possible dependence.
Our method 1) can learn an arbitrary form of the representation function from
the neighborhood, withour losing any potential dependence structures, and 2) is
applicable to both homogeneous and heterogeneous graph embedding, the latter of
which is challenged by the diversity of node types. Furthermore, we provide
theoretical guarantee for the representation capability of our method for
general homogeneous and heterogeneous graphs. Empirical evaluation results on
benchmark data sets show that our proposed PINE method outperforms the
state-of-the-art approaches on producing node vectors for various learning
tasks of both homogeneous and heterogeneous graphs.Comment: 24 pages, 4 figures, 3 tables. arXiv admin note: text overlap with
arXiv:1805.1118
{μ-trans-N,N′-Bis[(diphenylphosphanyl)methyl]benzene-1,4-diamine-κ2 P:P′}bis{(acetonitrile-κN)[dipyrido[3,2-a:2′,3′-c]phenazine-κ2 N 4,N 5]copper(I)} bis(tetrafluoridoborate)
In the centrosymmetric dinuclear title compound, [Cu2(C2H3N)2(C18H10N4)2(C32H30N2P2)](BF4)2, the CuI centre is coordinated by two N atoms from a dipyridophenazine ligand, one P atom from an N,N′-bis[(diphenylphosphanyl)methyl]benzene-1,4-diamine (bpbda) ligand, and one N atom from an acetonitrile molecule in a distorted tetrahedral geometry. The bpbda ligand, lying on an inversion center, bridges two CuI centres into a Z-shaped complex. Intramolecular π–π interactions between the dipyridophenazine ligand and the benzene ring of the bpbda ligand are observed [centroid–centroid distance = 3.459 (3) Å]. The crystal structure also involves intermolecular π–π interactions between the dipyridophenazine ligands [centroid–centroid distance = 3.506 (3) Å], which lead to a one-dimensional supramolecular structure
Poly[[hemi-μ4-oxalato-hemi-μ2-oxalato-bis(μ3-pyrazine-2-carboxylato)erbium(III)silver(I)] monohydrate]
The asymmetric unit of the title complex, {[AgEr(C5H3N2O2)2(C2O4)]·H2O}n, contains one ErIII atom, one AgI atom, two pyrazine-2-carboxylate (pyc) ligands, two half oxalate ligands (each lying on an inversion center) and one uncoordinated water molecule. The ErIII atom is coordinated by two O atoms and two N atoms from two pyc ligands, one O atom from a third pyc ligand and four O atoms from two oxalate ligands in a distorted monocapped square-antiprismatic geometry. The AgI atom is coordinated by two N atoms from two pyc ligands, one O atom from a third pyc ligand and one O atom from one oxalate ligand. The crystal structure exhibits a three-dimensional heterometallic polymeric network. O—H⋯O hydrogen bonding between the uncoordinated water molecule and carboxylate O atoms is observed
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