Type Crystal Structure Research Articles

Predicting synthesizability of crystalline materials via deep learning

Predicting the synthesizability of hypothetical crystals is challenging because of the wide range of parameters that govern materials synthesis. Yet, exploring the exponentially large space of novel crystals for any future application demands an accurate predictive capability for synthesis likelihood to avoid a haphazard trial-and-error. Typically, benchmarks of synthesizability are defined based on the energy of crystal structures. Here, we take an alternative approach to select features of synthesizability from the latent information embedded in crystalline materials. We represent the atomic structure of crystalline materials by three-dimensional pixel-wise images that are color-coded by their chemical attributes. The image representation of crystals enables the use of a convolutional encoder to learn the features of synthesizability hidden in structural and chemical arrangements of crystalline materials. Based on the presented model, we can accurately classify materials into synthesizable crystals versus crystal anomalies across a broad range of crystal structure types and chemical compositions. We illustrate the usefulness of the model by predicting the synthesizability of hypothetical crystals for battery electrode and thermoelectric applications.

Field-induced anomalous magnetic state beyond the magnetically ordered state in the slightly distorted triangular S=12 rare-earth antiferromagnet CeZn3P3

Magnetic properties of ${\mathrm{CeZn}}_{3}{\mathrm{P}}_{3}$, which has been believed to have the same hexagonal ${\mathrm{ScAl}}_{3}{\mathrm{C}}_{3}$-type crystal structure as that of a spin dimer system of ${\mathrm{YbAl}}_{3}{\mathrm{C}}_{3}$ at room temperature, have been investigated by magnetization, magnetostriction, specific heat ($C$), and magnetocaloric effect measurements. In this research, we have found that ${\mathrm{CeZn}}_{3}{\mathrm{P}}_{3}$ certainly has a slightly deformed crystal structure from the hexagonal one even at room temperature, which is in contrast to the structural phase transition of ${\mathrm{YbAl}}_{3}{\mathrm{C}}_{3}$ occuring at around 80 K, although the very slight deformation along the $c$ plane, i.e., slightly deformed triangular lattice, and the formation of the multidomain structure are common to both compounds. ${\mathrm{CeZn}}_{3}{\mathrm{P}}_{3}$ is thought to maintain its deformed structure from a high-temperature region above room temperature to an extremely low-temperature region and shows a magnetic order below ${T}_{\mathrm{N}}=0.8$ K. The analysis of the temperature dependence of the magnetic susceptibility ($\ensuremath{\chi}$) and $C$ has revealed that a Kramers doublet ground state with an easy-plane type anisotropy on the $c$ plane is well isolated from the excited states by the crystal field splitting energy of more than 300 K. Above ${T}_{\mathrm{N}}, \ensuremath{\chi}$ makes a broad peak at around 2 K, which certainly originates from the dimer formation due to the slight deformation of the triangular lattice. On the other hand, below ${T}_{\mathrm{N}}$, a magnetic phase diagram reminiscent of a magnetic flower blooming on the $c$ plane was observed, which may have a close relation to a quantum effect of a quasi $S=\frac{1}{2}$ spin system and a contribution of the orbital component. With increasing magnetic field, we have found an anomalous magnetic state beyond the usual magnetically ordered state, where $C/T$ is anomalously enhanced. This anomalous magnetic state is similar to that observed in ${\mathrm{YbAl}}_{3}{\mathrm{C}}_{3}$ induced by the field, although the magnetic ground state in ${\mathrm{YbAl}}_{3}{\mathrm{C}}_{3}$ is a nonmagnetic dimer state different from the normal magnetically ordered state in ${\mathrm{CeZn}}_{3}{\mathrm{P}}_{3}$.

Symmetry and chirality in crystals

A classification scheme relating the chirality of molecules to the type of crystal structures (chiral or achiral) they may form is presented. With respect to similar classifications proposed in the past, some corrections and extensions are introduced. In particular, (1) it is shown that chiral crystal structures from achiral molecules can occur in 28 types of space group having screw axes np , with p ≠ n/2, not in any Sohncke type of space group; (2) it is shown that the restriction on Z′ > 1 for kryptoracemates is contradicted by examples with Z′ = 1; and (3) the case of scalemic enantioenriched solutions, absent from most classifications, is included. Chiral crystal structures from purely inorganic (non-molecular) compounds are addressed too.

Isostructural M 2pt (M = Al, Ga, In, Sn) As OER Anode Materials

Looking for the future energy infrastructure, hydrogen will play an important role as energy carrier molecule. Among different physical and chemical methods of hydrogen production, water electrolysis has numerous advantages. However, the sluggish kinetics of anodic oxygen evolution reaction (OER) hinders its large-scale implementation. The intensive search for new OER electrocatalytic materials is limited by harsh oxidative conditions and instability/ changes of electrocatalyst under reaction conditions. Platinum is characterized by pronounced stability against dissolution compared to other noble metals. However, the OER activity of Pt is one of the lowest one. Combining the platinum with main group elements in form of M 2Pt intermetallic compound will lead to the different electronic state of Pt and, correspondingly, different OER activity.The compounds M2 Pt (M = Al, Ga, In, Sn) crystallize with cubic anti-CaF2 type of crystal structure [1]. Due to the pronounced charge transfer from M to Pt, Pt atoms are negatively charged in these compounds. There is only one type of strongly polar covalent interactions between M and Pt atoms. The OER activity decreases in the following sequence In2Pt > Ga2Pt > Al2Pt. This trend is governed by the chemical nature of the counterpart elements M (M = Al, Ga, In) and their leaching rates under OER conditions. The leaching of M into the electrolyte leads to formation of composite material of intermetallic M2 Pt and Pt-rich phase in the near-surface region. The inactivity of Sn2Pt is due to the formation of passivating SnO2 layer with poor electrical conductivity.The study of OER activity of M 2Pt materials under different electrochemical treatments was combined with surface- and bulk characterization of electrodes after electrochemical experiments, elemental analysis of electrolyte and quantum chemical calculations. This allows to investigate the influence of chemical nature of counterpart element M onto the OER performance of isostructural M 2Pt electrode materials [2].[1]. Antonyshyn, I., Barrios Jiménez, A.M., Sichevych, O., Burkhardt, U., Veremchuk, I., Schmidt, M., Ormeci, A., Spanos, I., Tarasov, A., Teschner, D., Algara-Siller, G., Schlögl, R., Grin, Yu. // Angew. Chem. Int. Ed. 59, 16770–16776 (2020).[2]. Barrios Jiménez, A.M., Burkhardt, U., Altendorf, S.G., Kaiser, F., Veremchuk, I., Ormeci, A., Auffermann, G., Antonyshyn, I., Grin, Yu., submitted.

Chirality and Magnetocaloricity in GdFeTeO6 as Compared to GdGaTeO6.

GdFeTeO6 and GdGaTeO6 have been prepared and their structures refined by the Rietveld method. Both are superstructures of the rosiaite type (space group ). Their thermodynamic properties have been investigated by means of magnetization M and specific heat Cp measurements, evidencing the formation of the long-range antiferromagnetic order at TN = 2.4 K in the former compound and paramagnetic behavior down to 2 K in the latter compound. Large magnetocaloric effect allows considering GdFeTeO6 for the magnetic refrigeration at liquid hydrogen stage. Density functional theory calculations produce estimations of leading Gd–Gd, Gd–Fe and Fe–Fe interactions suggesting unique chiral 120° magnetic structure of Fe3+ (S = 5/2) moments and Gd3+ (J = 7/2) moments rotating in opposite directions (clockwise/anticlockwise) within weakly coupled layers of the rosiaite type crystal structure.

Python-based Program for Analysing Lattice Parameter of Cubic and Tetragonal Crystal Structure

A program for analysing lattice parameter of a crystal structure has been successfully created based on Python programming language using the Google Collaboratory service, so it can be accessed through a PC or smartphone as long as internet access is available. This program can be used to calculate lattice parameter of a crystal structure with x-ray diffraction data as the input. Crystal structures that can be calculated for its lattice parameter are cubic and tetragonal. The program will ask for the type of crystal structure of the data, along with diffraction angles and miller indices. The input will be processed using the Cramer-Cohen method according to the previously entered crystal structure. By also entering the wavelength used, the output of this program is the lattice parameter in the angstrom unit. The percentage of error of this program’s output is extremely low.

Copper Crystal Structures in Plated Microvias. Their Recrystallisation and a Means to Identify Joints at Risk of Premature Failure

Abstract Plated microvias are widely used within todays PCB industry as a means of achieving the high-density designs that are required in modern mobile devices, however, there has been growing concern regarding their long term reliability performance when stacked directly on top of each other. Blind microvias (BMV) have a potentially complex metallurgical structure, with several interfaces located around the target pad - electroless Copper - electrolytic Copper joint. While field experience as shown that there are typically two major types of crystal structures formed across the BMV base, there has been little reported work investigating how or why such structures develop. In this paper, we review these two commonly observed microstructures within filled BMVs and offer proposals on how such structures are created. We subsequently describe a novel means to indicate if the microstructure of a BMV is likely to have a tendency for an early onset of failure.

Titanium Dioxide in Commercial Sunscreens: the Morphological Characterization and the Quantification

<p class='IJASEITAbtract'>Due to nanotechnology's advancement, the application of nanomaterials in commercial products, including in sunscreens, has been increased rapidly. Physical sunscreens employ Titanium dioxide (TiO₂) or Zinc oxide (ZnO) nanoparticles as UV filter materials. Indonesian National Agency of Drug and Food Control regulates that TiO₂ rutile polymorph, size distribution ≥30 nm, and maximum concentration of 25% are criteria for physical sunscreen marketed in Indonesia. However, most of these products do not indicate the detailed inorganic material information in the product ingredients, resulting in the increasing concern of nanoparticle’s risk to human health and the environment. Therefore, the size, type of crystal structure, and amount of TiO2 or ZnO must be closely monitored. In this work, we investigated the morphological structure of TiO_2, including quantified its concentration in some commercial sunscreens marketed in Indonesia. TiO₂ was characterized using different characterization techniques. XRD analysis revealed that some studied sunscreens employed anatase TiO_2, which is not suggested to be added in a sunscreen product. HRTEM analysis proved that the sizes of materials in sample S1-S3 are below 50 nm, and silica-coated TiO₂ was observed in S4. Quantification of Titanium using GF-AAS yielded Ti's concentration in the range of 1400-7800 µg g^-1 (0.14-0.79%). To the best of our knowledge, this is the first study to report the physical properties and the concentration of TiO₂ nanoparticles (NPs) in commercial sunscreen marketed in Indonesia.

HoF(OH)2: a fluoride-containing holmium(III) hydroxide with UCl3-type crystal structure

HoF(OH)₂: a fluoride-containing holmium(III) hydroxide with UCl₃-type crystal structure

Investigation of irradiation resistance characteristics of precipitation strengthened high-entropy alloy (CoCrFeNi)95Ti1Nb1Al3 using slow positron beam

A high-entropy alloy (HEA), (CoCrFeNi)95Ti1Nb1Al3, with a tensile strength approximately 60% higher than that of the equiatomic high-entropy alloy CoCrFeNi was developed. The increase in tensile strength results from the formation of Ni, Ti, Nb, and Al-rich precipitates, having a face-centered cubic (FCC) L12 type crystal structure, in the alloy during aging. To investigate the irradiation resistance of this alloy, it was irradiated up to 1.5×1019 ions/m2, corresponding to 1.65 displacements per atom (dpa) at the peak damage, at 300, 573, and 773 K using high-energy 2.5 MeV Fe ions. Applying a slow positron beam, the formation of defect clusters induced by ion irradiation and the thermal stability of defects formed at 300 K were investigated. Vacancy clusters formed after irradiation with 5.0×1018 ions/m2 at 300 K. Irradiation above this fluence at 300 K, and at the same fluence at 573 K did not significantly affect the formation of vacancy clusters. However, no vacancy clusters were formed after irradiation at 5.0×1018 ions/m2 at 773 K. The high-temperatures irradiation of this HEA hinders the formation of vacancy clusters. The irradiation resistance of the (CoCrFeNi)95Ti1Nb1Al3 HEA was excellent.

Exploring the Activation Process of the β2AR-Gs Complex.

G-Protein-coupled receptors (GPCRs) belong to an important family of integral membrane receptor proteins that are essential for a variety of transmembrane signaling process, such as vision, olfaction, and hormone responses. They are also involved in many human diseases (Alzheimer's, heart diseases, etc.) and are therefore common drug targets. Thus, understanding the details of the GPCR activation process is a task of major importance. Various types of crystal structures of GPCRs have been solved either at stable end-point states or at possible intermediate states. However, the detailed mechanism of the activation process is still poorly understood. For example, it is not completely clear when the nucleotide release from the G protein occurs and how the key residues on α5 contribute to the coupling process and further affect the binding specificity. In this work we show by free energy analysis that the guanosine diphosphate (GDP) molecule could be released from the Gs protein when the binding cavity is half open. This occurs during the transition to the Gs open state, which is the rate-determining step in the system conformational change. We also account for the experimentally observed slow-down effects by the change of the reaction barriers after mutations. Furthermore, we identify potential key residues on α5 and validated their significance by site-directed mutagenesis, which illustrates that computational works have predictive value even for complex biophysical systems. The methodology of the current work may be applied to other biophysical systems of interest.

Drastic reduction of the R -Fe exchange in interstitially modified (Nd,Ho)2Fe14B compounds probed by megagauss magnetic fields

In this paper, the full magnetization process demonstrated by the series of ferrimagnetic intermetallic compounds ${(\mathrm{Nd},\mathrm{Ho})}_{2}{\mathrm{Fe}}_{14}\mathrm{B}$ and ${\mathrm{Ho}}_{2}{\mathrm{Fe}}_{14}\mathrm{B}$ and their hydrides with the maximum possible hydrogen content (for the given crystal structure type) is studied theoretically and experimentally using megagauss magnetic fields. We observe field-induced phase transitions from the initial ferrimagnetic to the forced-ferromagnetic state in magnetic fields up to 130 T and describe the magnetization process analytically. We find a drastic decrease of the critical transition fields in the hydrogenated compounds. This is due to extremely strong, nearly twofold reduction of the $R$-Fe intersublattice exchange interaction because of the combined substitution and hydrogenation effects. A comparative analysis of the magnetization behavior for the system ${\mathrm{Ho}}_{2}{\mathrm{Fe}}_{17}\text{\ensuremath{-}}\mathrm{H}$ is also performed.

Machine learning based prediction of lattice thermal conductivity for half-Heusler compounds using atomic information

Half-Heusler compound has drawn attention in a variety of fields as a candidate material for thermoelectric energy conversion and spintronics technology. When the half-Heusler compound is incorporated into the device, the control of high lattice thermal conductivity owing to high crystal symmetry is a challenge for the thermal manager of the device. The calculation for the prediction of lattice thermal conductivity is an important physical parameter for controlling the thermal management of the device. We examined whether lattice thermal conductivity prediction by machine learning was possible on the basis of only the atomic information of constituent elements for thermal conductivity calculated by the density functional theory in various half-Heusler compounds. Consequently, we constructed a machine learning model, which can predict the lattice thermal conductivity with high accuracy from the information of only atomic radius and atomic mass of each site in the half-Heusler type crystal structure. Applying our results, the lattice thermal conductivity for an unknown half-Heusler compound can be immediately predicted. In the future, low-cost and short-time development of new functional materials can be realized, leading to breakthroughs in the search of novel functional materials.

Crystal structure of the ferredoxin reductase component of carbazole 1,9a-dioxygenase from Janthinobacterium sp. J3.

Carbazole 1,9a-dioxygenase (CARDO), which consists of an oxygenase component and the electron-transport components ferredoxin (CARDO-F) and ferredoxin reductase (CARDO-R), is a Rieske nonheme iron oxygenase (RO). ROs are classified into five subclasses (IA, IB, IIA, IIB and III) based on their number of constituents and the nature of their redox centres. In this study, two types of crystal structure (type I and type II) were resolved of the class III CARDO-R from Janthinobacterium sp. J3 (CARDO-RJ3). Superimposition of the type I and type II structures revealed the absence of flavin adenine dinucleotide (FAD) in the type II structure along with significant conformational changes to the FAD-binding domain and the C-terminus, including movements to fill the space in which FAD had been located. Docking simulation of NADH into the FAD-bound form of CARDO-RJ3 suggested that shifts of the residues at the C-terminus caused the nicotinamide moiety to approach the N5 atom of FAD, which might facilitate electron transfer between the redox centres. Differences in domain arrangement were found compared with RO reductases from the ferredoxin-NADP reductase family, suggesting that these differences correspond to differences in the structures of their redox partners ferredoxin and terminal oxygenase. The results of docking simulations with the redox partner class III CARDO-F from Pseudomonas resinovorans CA10 suggested that complex formation suitable for efficient electron transfer is stabilized by electrostatic attraction and complementary shapes of the interacting regions.

Large Orbital Magnetic Moment and Strong Perpendicular Magnetic Anisotropy in Heavily Intercalated FexTiS2

Titanium disulfide TiS$_2$, which is a member of the layered transition-metal dichalcogenides with the 1T-CdI$_2$-type crystal structure, is known to exhibit a wide variety of magnetism through intercalating various kinds of transition-metal atoms of different concentrations. Among them, Fe-intercalated titanium disulfide Fe$_x$TiS$_2$ is known to be ferromagnetic with strong perpendicular magnetic anisotropy (PMA) and large coercive fields ($H_\text{c}$). In order to study the microscopic origin of the magnetism of this compound, we have performed X-ray absorption spectroscopy (XAS) and X-ray magnetic circular dichroism (XMCD) measurements on single crystals of heavily intercalated Fe$_x$TiS$_2$ ($x\sim0.5$). The grown single crystals showed a strong PMA with a large $H_\text{c}$ of $\mu_0H_\text{c} \simeq 1.0\ \text{T}$. XAS and XMCD spectra showed that Fe is fully in the valence states of 2+ and that Ti is in an itinerant electronic state, indicating electron transfer from the intercalated Fe atoms to the host TiS$_2$ bands. The Fe$^{2+}$ ions were shown to have a large orbital magnetic moment of $\simeq 0.59\ \mu_\text{B}\text{/Fe}$, to which, combined with the spin-orbit interaction and the trigonal crystal field, we attribute the strong magnetic anisotropy of Fe$_x$TiS$_2$.

Comprehensive study of changes in the optical, structural and strength properties of ZrO2 ceramics as a result of phase transformations caused by irradiation with heavy ions

This work is devoted to the study of the effect of irradiation with Kr15+ and Xe23+ heavy ions with energies of 147 and 220 MeV, respectively, on the change in the optical, structural and strength properties of ceramics ZrO2. Polycrystalline ZrO2 ceramics with a tetragonal type of crystal structure, which are highly resistant to external influences, mechanical strength to cracking, and hardness were chosen as the object of research. The choice of heavy ions Kr15+ and Xe23+ is due to the possibility of simulating the effect of nuclear fission fragments in an atomic reactor, and the choice of irradiation doses of 1 × 1013–1 × 1014 ion/cm2 is due to the possibility of simulating the effects of overlapping defect regions arising along the trajectory of ions in the material. Using the X-ray diffraction method, it was found that in the case of irradiation with heavy ions, an increase in the radiation dose leads to phase transformations of the tetragonal type of the crystal lattice into a cubic one. In this case, for the samples irradiated with Xe23+ ions at an irradiation dose of 1 × 1014 ion/cm2, an almost complete phase transformation is observed. Dependences of changes in strength and optical characteristics on the type of irradiation and dose load have been established.

An update on the mineral-like Sr-containing transition metal arsenates

AbstractWe report on the crystal structures of three novel synthetic SrM-arsenates (M = Ni and Fe3+), isostructural or structurally related to the minerals from tsumcorite, carminite and brackebuschite groups. They were synthesised under mild hydrothermal conditions and further characterised using single-crystal X-ray diffraction (SXRD), scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) and Raman spectroscopy. SXRD and SEM-EDS yielded formulae: (I) SrNi2(AsO4)2⋅2H2O, (II) Sr1.4Fe3+1.6(AsO4)2(OH)1.6 and (III) SrFe3+(AsO4)(AsO3OH). All three structures are built up of slightly distorted MO6 octahedra and AsO4 tetrahedra that are linked by Sr2+ with different coordination geometries and hydrogen bonds. I represent a basic structure type typical for tsumcorite-group minerals (space group C2/m) while II has a new intermediate structure between carminite, PbFe3+2(AsO4)2(OH)2 and arsenbrackebuschite, Pb2Fe3+(AsO4)2(OH) (s.g. Pm). III is triclinic and adopts a new structure-type (s.g. P$\bar{1}$). The structure of I is built up of infinite linear edge-sharing NiO4(OH2)2 octahedral chains, extending along [010] and linked by AsO4 tetrahedra, SrO8 polyhedra and hydrogen bonds. The structure of II is characterised by the carminite-like FeO4(OH)2 octahedral chains and Edshammar-polyhedral chains, which involves SrO11 coordination polyhedra similar to that of PbO11 in arsenbrackebuschite. Both chains in II are aligned parallel to the b axis of the monoclinic unit cell and connected together by the arsenate AsO4 tetrahedra, SrO8 polyhedra and the hydrogen-bonding network. The compound III has a new type of crystal structure based on the unusual corrugated octahedral–tetrahedral-quadruple chains. These are made up of a central double-sided chain linked to two single-sided chains into a quadruple chain extended along the a axis. The chains in III are built up of FeO6 octahedra and AsO4 tetrahedra further linked to each other by shared vertices. The quadruple chains are interconnected by additional AsO4 tetrahedra forming a heteropolyhedral 3D open framework. Strontium atoms are situated in the two channels. The structural connections to related minerals and inorganic compounds are discussed.

Mixed metal oxide pigments

Abstract Mixed metal oxide (MMO) pigments, also knowns as complex inorganic color pigments (CICPs), are an important class of inorganic pigments. They are representatives of the blue, green, yellow, brown, and black pigments. These pigments are called mixed complex because they contain two or more different metals in the composition. Their main advantages are high opacity, heat stability, useful infrared properties, light- and weather fastness, and chemical resistance. MMOs are solid solutions of metal oxides, which are homogenously distributed in their crystal lattices. They are based on different types of crystal structures, such as rutile, spinel, inverse spinel, hematite, priderite, and pseudobrookite. Other products belonging to the CICPs besides the rutile and spinel type MMOs are pigments based on zirconium silicate (zircon, ZrSiO4). Such compositions belong to the class of ceramic pigments (color stains for glazes).

Combined MD and QM/MM Investigations of Hydride Reduction of 5α-Dihydrotestosterone Catalyzed by Human 3α-Hydroxysteroid Dehydrogenase Type 3: Importance of Noncovalent Interactions.

3α-Hydroxysteroid dehydrogenase (3α-HSD) is an enzyme that is essential in the regulation of the concentration of 5α-dihydrotestosterone (5α-DHT) in the prostate. It catalyzes the hydride reduction of 5α-DHT to 3α-androstanediol, which activates androgen receptors. Elucidating details about the hydride reduction of 5α-DHT by 3α-HSD and the environment around the active site of the enzyme could lead to the development of effective drugs for the treatment of prostate cancer. In this study, the X-ray crystal structure of human 3α-HSD type 3 was comprehensively evaluated. Moreover, molecular dynamics (MD) simulations and hybrid ONIOM-type quantum mechanics/molecular mechanics (QM/MM) calculations were performed using a large QM region (maximum 232 atoms). It was determined that the reaction proceeded in a single step without the formation of an alkoxide ion owing to the direct hydride reduction of the substrate by nicotinamide adenine dinucleotide phosphate (NADPH) and concerted proton transfer by Tyr55 and Lys84. Noncovalent interaction (NCI) analysis highlighted the roles of Tyr216 and Trp227 in 3α-HSD. Specifically, Tyr216 assisted the reaction by π/π interactions with the neighboring nicotinamide ring of NADP(H), whereas Trp227 played an important role in recognition of the size of the substrate by CH/π interactions.

Assessing Local Environments in Green Fluorescent Protein using Unnatural Amino Acid 4‐Cyano‐L‐Phenylalanine

An increasingly useful method of studying local electrostatic environments within protein molecules is through the incorporation of unnatural amino acids (UAAs) containing distinguishable chemical bonds with specific features in the infrared spectrum (IR) that change based on local environments. Of the existing UAAs, 4-cyano-L-phenylalanine (pCNF) is arguably one of the most useful vibrational reporters due to the fact that it is easily and affordably synthesized, it is well-studied, and its nitrile stretch appears in a biologically quiet region of the IR spectrum. In this study, pCNF has been genetically incorporated individually into three distinct sites of superfolder green fluorescent protein (sfGFP) via the amber codon suppression methodology. According to the wild type crystal structure of sfGFP, each of the selected sites are expected to have a unique solvation environment. Temperature-dependent infrared (IR) spectroscopy was utilized in order to test assess the local solvation environments of each of these sites. By measuring the nitrile stretching frequency as a function of temperature, the degree to which the incorporated pCNF participates in hydrogen bonding was determined. IR data and X-ray crystal structures from these constructs will be presented.