International Journal of Innovation in Education, 2018
Students are at risk of struggling academically and socially in the first two semesters following... more Students are at risk of struggling academically and socially in the first two semesters following a transfer to a university setting. Helping transfer students in this critical period is complicated by a large variance in students' prerequisite knowledge. A flipped classroom with a large group work component may help students form cohort bonds; however, it is difficult to get groups of students comfortable enough to engage in such discussions. The purpose of this mixed method case study was to investigate how limiting groups' resources to a single smartpen and notebook helped students form a strong classroom community that integrates all students. Sixteen pre-service middle school teachers from seven different transfer institutions were enrolled in a flipped precalculus course using smartpens to record their activities. Findings indicated that the smartpens helped students build stronger cohort bonds and encouraged students to confront their own misconceptions about the material.
A set of six long-term, full-scale experiments were initiated to determine the type and extent of... more A set of six long-term, full-scale experiments were initiated to determine the type and extent of corrosion that occurs in 3013 containers packaged with chloride-bearing plutonium oxide materials. The materials were exposed to a high relative humidity environment representative of actual packaging conditions for the materials in storage. The materials were sealed in instrumented, inner 3013 containers with corrosion specimens designed to test the corrosiveness of the environment inside the containers under various conditions. This report focuses on initial loading conditions that are used to establish a baseline to show how the conditions change throughout the storage lifetime of the containers.
The Steadman Clinic RESUMEN. La osteoartritis del hombro ha sido considerada como una causa de do... more The Steadman Clinic RESUMEN. La osteoartritis del hombro ha sido considerada como una causa de dolor severo y de pérdida de la función del hombro. Muchos de los pacientes con osteoartritis de hombro son pacientes jóvenes y con actividades demandantes, por lo cual ponen en tela de duda la opción de una artroplastía. Es por esto que en este artículo describimos el manejo artroscópico integral (CAM, por sus siglas en inglés) que combina el desbridamiento artroscópico, la liberación capsular, la osteoplastía de la parte inferior de la cabeza humeral y la descompresión del nervio axilar. En nuestra experiencia, esta técnica ha mostrado resultados prometedores a corto plazo en pacientes, al disminuirles el dolor y regresándolos a actividades demandantes de alto nivel. Palabras clave: artritis, hombro, osteoplastía, descompresión, dolor. ABSTRACT. Shoulder osteoarthritis has been considered as a cause of severe pain and loss of shoulder function. Many patients with shoulder osteoarthritis are young and have demanding activities, which leads to questioning the choice of arthroplasty. This is why in this paper we describe the comprehensive arthroscopic management (CAM) that combines arthroscopic debridement, capsular release, osteoplasty of the lower humeral head, and auxiliary nerve decompression. In our experience this technique has shown short-term promising results as it decreases pain and allows patients to resume high performance demanding activities.
tion HIV-specific CD8 T cells selectively expressed high levels of the pro-apoptotic marker CD95,... more tion HIV-specific CD8 T cells selectively expressed high levels of the pro-apoptotic marker CD95, low anti-apoptotic molecule BCL-2 and failed to upregulate the IL-7 receptor. Overnight in vitro incubation of peak activation CD8 T cells resulted in high levels of spontaneous cell death compared to cells collected after the resolution of T cell activation. Furthermore, activated CD8 T cells were also less responsive to ex vivo stimulation compared to samples collected after resolution of activation, suggesting maximal in vivo activation. Conclusions: These data indicate that primary HIV infection induces massive CD8 T cell expansion, which declines despite persistence of detectable viremia. The disappearance of early responses may be attributed to persistent elevation of antigenstimulation driving virus-specific cells towards apoptosis. Therefore strategies aimed at blocking apoptosis might be a viable option for rescuing or strengthening early responses.
The subscapularis tendon is an important anatomic structure of the shoulder joint and is necessar... more The subscapularis tendon is an important anatomic structure of the shoulder joint and is necessary for an unimpaired shoulder function. Subscapularis tendon lesions frequently need treatment to preserve shoulder function. This article provides an overview of the current treatment of subscapularis tears and details the specific techniques.
Coracoplasty has become a more commonly performed surgical procedure, as coracoid impingement has... more Coracoplasty has become a more commonly performed surgical procedure, as coracoid impingement has become increasingly recognized as a cause of persistent anterior shoulder pain. Open and arthroscopic techniques have shown satisfactory results. This article will provide a current review about the indications and techniques for coracoplasy, including both arthroscopic and open techniques and the expected outcomes.
The Ensembl project (http://www.ensembl.org) provides genome resources for chordate genomes with ... more The Ensembl project (http://www.ensembl.org) provides genome resources for chordate genomes with a particular focus on human genome data as well as data for key model organisms such as mouse, rat and zebrafish. Five additional species were added in the last year including gibbon (Nomascus leucogenys) and Tasmanian devil (Sarcophilus harrisii) bringing the total number of supported species to 61 as of Ensembl release 64 (September 2011). Of these, 55 species appear on the main Ensembl website and six species are provided on the Ensembl preview site (Pre!Ensembl; http://pre .ensembl.org) with preliminary support. The past year has also seen improvements across the project.
For many years, coracoid impingement has been a well-recognized cause of anterior shoulder pain. ... more For many years, coracoid impingement has been a well-recognized cause of anterior shoulder pain. However, a precise diagnosis of coracoid impingement remains difficult in some cases due to the presence of multifactorial pathologies and a paucity of supporting evidence in the literature. This review provides an update on the current anatomical and biomechanical knowledge regarding this pathology, describes the diagnostic process, and discusses the possible treatment options, based on a systematic review of the literature. Level of evidence V.
Journal of The American Society for Mass Spectrometry, 2011
Electrospray ionization of actinyl perchlorate solutions in H 2 O with 5% by volume of dimethylfo... more Electrospray ionization of actinyl perchlorate solutions in H 2 O with 5% by volume of dimethylformamide (DMF) produced the isolatable gas-phase complexes, [An VI O 2 (DMF) 3 (H 2 O)] 2+ and [An VI O 2 (DMF) 4 ] 2+ , where An = U, Np, and Pu. Collision-induced dissociation confirmed the composition of the dipositive coordination complexes, and produced doubly-and singly-charged fragment ions. The fragmentation products reveal differences in underlying chemistries of uranyl, neptunyl, and plutonyl, including the lower stability of Np(VI) and Pu(VI) compared with U(VI).
Reported here is a comparison of electron transfer dissociation (ETD) and collision-induced disso... more Reported here is a comparison of electron transfer dissociation (ETD) and collision-induced dissociation (CID) of solvent-coordinated dipositive uranyl and plutonyl ions generated by electrospray ionization. Fundamental differences between the ETD and CID processes are apparent, as are differences between the intrinsic chemistries of uranyl and plutonyl. Reduction of both charge and oxidation state, which is inherent in ETD activation of [An(VI) O(2) (CH(3) COCH(3) )(4) ](2+) , [An(VI) O(2) (CH(3) CN)(4) ](2) , [U(VI) O(2) (CH(3) COCH(3) )(5) ](2+) and [U(VI) O(2) (CH(3) CN)(5) ](2+) (An = U or Pu), is accompanied by ligand loss. Resulting low-coordinate uranyl(V) complexes add O(2) , whereas plutonyl(V) complexes do not. In contrast, CID of the same complexes generates predominantly doubly-charged products through loss of coordinating ligands. Singly-charged CID products of [U(VI) O(2) (CH(3) COCH(3) )(4,5) ](2+) , [U(VI) O(2) (CH(3) CN)(4,5) ](2+) and [Pu(VI) O(2) (CH(3) CN)(4) ](2+) retain the hexavalent metal oxidation state with the addition of hydroxide or acetone enolate anion ligands. However, CID of [Pu(VI) O(2) (CH(3) COCH(3) )(4) ](2+) generates monopositive plutonyl(V) complexes, reflecting relatively more facile reduction of Pu(VI) to Pu(V).
The salts-yellow [Cr(NH 3) 6 ][Ag(CN) 2 ] 3 AE 2H 2 O, red [Co(NH 3) 6 ][Ag(CN) 2 ] 3 AE 2H 2 O, ... more The salts-yellow [Cr(NH 3) 6 ][Ag(CN) 2 ] 3 AE 2H 2 O, red [Co(NH 3) 6 ][Ag(CN) 2 ] 3 AE 2H 2 O, red [Co(NH 3) 6 ][Au(CN) 2 ] 3 AE 2H 2 O, pale yellow [Ru(NH 3) 6 ][Ag(CN) 2 ] 3 AE 2H 2 O, yellow K[Cr(NH 3) 6 ] 2 [Au(CN) 2 ] 7 AE 4H 2 O, and colorless [(l 2-NH 2) 2 Pt 2 (NH 3) 10 ][Au(CN) 2 ] 6 AE 5.5{OS(CH 3) 2 } AE 0.5H 2 O-have been prepared by evaporation of aqueous solutions of potassium dicyanoargenate or potassium dicyanoaurate and salts of the appropriate cations. Hydrogen bonding between the cations and the cyano groups of the anions facilitates the formation of structures with strong metallophilic interactions between the anions. Thus, the [Au(CN) 2 ] À or [Ag(CN) 2 ] À ions self-associate into linear trimers in the isostructural set of crystals, [Cr(NH 3) 6 ][Ag(CN) 2 ] 3 AE 2H 2 O (AgÁ Á ÁAg distance; 3.1610(4) Å), [Co(NH 3) 6 ][Ag(CN) 2 ] 3 AE 2H 2 O (AgÁ Á ÁAg distance; 3.1557(2) Å), [Co(NH 3) 6 ][Au(CN) 2 ] 3 AE 2H 2 O (AuÁ Á ÁAu distance; 3.0939(4) Å), and [Ru(NH 3) 6 ][Ag(CN) 2 ] 3 AE 2H 2 O (AgÁ Á ÁAg distance; 3.1584(5) Å). Crystalline [(l 2-NH 2) 2 Pt 2 (NH 3) 10 ][Au(CN) 2 ] 6 AE 5.5{OS(CH 3) 2 } AE 0.5H 2 O also contains nearly linear trimers of the dicyanoaurate ion. Yellow crystals of K[Cr(NH 3) 6 ] 2 [Au(CN) 2 ] 7 AE 4H 2 O contain a centrosymmetric, bent chain of seven dicyanoaurate ions with AuÁ Á ÁAu separations of 3.1806(3), 3.2584(4), and 3.1294(4) Å .
Recent gas-phase experimental studies suggest the presence of hypercoordinated uranyl complexes. ... more Recent gas-phase experimental studies suggest the presence of hypercoordinated uranyl complexes. Coordination of acetone (Ace) to uranyl to form hypercoordinated species is examined using density functional theory (DFT) with a range of functionals and second-order perturbation theory (MP2). Complexes with up to eight acetones were studied. It is shown that no more than six acetones can bind directly to uranium and that the observed uranyl complexes are not hypercoordinated. In addition, other more exotic species involving proton transfer between acetones and species involving enol tautomers of acetone are high-energy species that are unlikely to form.
The metalloligand [Au{C(NHMe)(NHCH 2 CH 2 NH 2)} 2 ]Cl, 1, has been prepared by the reaction of e... more The metalloligand [Au{C(NHMe)(NHCH 2 CH 2 NH 2)} 2 ]Cl, 1, has been prepared by the reaction of ethylenediamine with [Au(CNMe) 2 ]Cl. Compound 1 crystallized as a luminescent dimer with a Au 3 3 3 Au separation of 3.0224(4) Å. It reacted in solution with silver hexafluorophosphate to form the coordination polymer, {[Au{ μ-C(NHMe)(NHCH 2 CH 2 NH 2)} 2 Ag (NCMe)](PF 6) 2 } n , 2. The structure of 2 involves a chain of alternating gold(I) and silver(I) ions with a Au 3 3 3 Ag distance of 2.9694(4) Å. The reaction of the metalloligand, 1, with silver tetrafluoroborate yielded three products: the green luminescent coordination polymer, {[Au{ μ-C(NHMe)(NHCH 2 CH 2 NH 2)} 2 Ag-(NCMe)](BF 4) 2 } n , 3, which is analogous to 2; the non-luminescent binuclear complex, [Au{ μ-C(NHMe)(NHCH 2 CH 2 NH 2)} 2 Ag](BF 4) 2 , 4; and the blue luminescent complex, [{ μ-C(NHMe)NHCH 2 CH 2 NH(MeHN)C}Au 2 { μ-C(NHMe)(NHCH 2 CH 2 NH 2)} 2 Ag](BF 4) 3-3 3(MeCN), 5. Compound 5 involves a bent Au 3 3 3 Ag 3 3 3 Au cation with two different Au 3 3 3 Ag distances (2.9165(8) Å and 3.1743(8) Å). This cation self-associates through a Au 3 3 3 Au interaction of 3.0275(5) Å , which allows the formation of an extended zigzag chain of cations in 5.
The preparation and X-ray crystal structures of (CyNC)Au I CN, (n-BuNC)Au I CN, and (i-PrNC)Au I ... more The preparation and X-ray crystal structures of (CyNC)Au I CN, (n-BuNC)Au I CN, and (i-PrNC)Au I CN‚0.5CH 2 Cl 2 are reported and compared with those of (MeNC)Au I CN and (t-BuNC)Au I CN, which were previously described. These linear molecules are all organized through aurophilic interactions into three structural classes: simple chains ((CyNC)-Au I CN and (t-BuNC)Au I CN), side-by-side chains in which two strands make Au‚‚‚Au contact with each other ((n-BuNC)Au I CN), and nets in which multiple aurophilic interactions produce layers of gold(I) centers ((i-PrNC)Au I CN and (MeNC)Au I CN). All of these five solids dissolve to produce colorless, nonluminescent solutions with similar UV/vis spectra. However, each of the solids displays a unique luminescence with emission maxima occurring in the range 371−430 nm.
International Journal of Innovation in Education, 2018
Students are at risk of struggling academically and socially in the first two semesters following... more Students are at risk of struggling academically and socially in the first two semesters following a transfer to a university setting. Helping transfer students in this critical period is complicated by a large variance in students' prerequisite knowledge. A flipped classroom with a large group work component may help students form cohort bonds; however, it is difficult to get groups of students comfortable enough to engage in such discussions. The purpose of this mixed method case study was to investigate how limiting groups' resources to a single smartpen and notebook helped students form a strong classroom community that integrates all students. Sixteen pre-service middle school teachers from seven different transfer institutions were enrolled in a flipped precalculus course using smartpens to record their activities. Findings indicated that the smartpens helped students build stronger cohort bonds and encouraged students to confront their own misconceptions about the material.
A set of six long-term, full-scale experiments were initiated to determine the type and extent of... more A set of six long-term, full-scale experiments were initiated to determine the type and extent of corrosion that occurs in 3013 containers packaged with chloride-bearing plutonium oxide materials. The materials were exposed to a high relative humidity environment representative of actual packaging conditions for the materials in storage. The materials were sealed in instrumented, inner 3013 containers with corrosion specimens designed to test the corrosiveness of the environment inside the containers under various conditions. This report focuses on initial loading conditions that are used to establish a baseline to show how the conditions change throughout the storage lifetime of the containers.
The Steadman Clinic RESUMEN. La osteoartritis del hombro ha sido considerada como una causa de do... more The Steadman Clinic RESUMEN. La osteoartritis del hombro ha sido considerada como una causa de dolor severo y de pérdida de la función del hombro. Muchos de los pacientes con osteoartritis de hombro son pacientes jóvenes y con actividades demandantes, por lo cual ponen en tela de duda la opción de una artroplastía. Es por esto que en este artículo describimos el manejo artroscópico integral (CAM, por sus siglas en inglés) que combina el desbridamiento artroscópico, la liberación capsular, la osteoplastía de la parte inferior de la cabeza humeral y la descompresión del nervio axilar. En nuestra experiencia, esta técnica ha mostrado resultados prometedores a corto plazo en pacientes, al disminuirles el dolor y regresándolos a actividades demandantes de alto nivel. Palabras clave: artritis, hombro, osteoplastía, descompresión, dolor. ABSTRACT. Shoulder osteoarthritis has been considered as a cause of severe pain and loss of shoulder function. Many patients with shoulder osteoarthritis are young and have demanding activities, which leads to questioning the choice of arthroplasty. This is why in this paper we describe the comprehensive arthroscopic management (CAM) that combines arthroscopic debridement, capsular release, osteoplasty of the lower humeral head, and auxiliary nerve decompression. In our experience this technique has shown short-term promising results as it decreases pain and allows patients to resume high performance demanding activities.
tion HIV-specific CD8 T cells selectively expressed high levels of the pro-apoptotic marker CD95,... more tion HIV-specific CD8 T cells selectively expressed high levels of the pro-apoptotic marker CD95, low anti-apoptotic molecule BCL-2 and failed to upregulate the IL-7 receptor. Overnight in vitro incubation of peak activation CD8 T cells resulted in high levels of spontaneous cell death compared to cells collected after the resolution of T cell activation. Furthermore, activated CD8 T cells were also less responsive to ex vivo stimulation compared to samples collected after resolution of activation, suggesting maximal in vivo activation. Conclusions: These data indicate that primary HIV infection induces massive CD8 T cell expansion, which declines despite persistence of detectable viremia. The disappearance of early responses may be attributed to persistent elevation of antigenstimulation driving virus-specific cells towards apoptosis. Therefore strategies aimed at blocking apoptosis might be a viable option for rescuing or strengthening early responses.
The subscapularis tendon is an important anatomic structure of the shoulder joint and is necessar... more The subscapularis tendon is an important anatomic structure of the shoulder joint and is necessary for an unimpaired shoulder function. Subscapularis tendon lesions frequently need treatment to preserve shoulder function. This article provides an overview of the current treatment of subscapularis tears and details the specific techniques.
Coracoplasty has become a more commonly performed surgical procedure, as coracoid impingement has... more Coracoplasty has become a more commonly performed surgical procedure, as coracoid impingement has become increasingly recognized as a cause of persistent anterior shoulder pain. Open and arthroscopic techniques have shown satisfactory results. This article will provide a current review about the indications and techniques for coracoplasy, including both arthroscopic and open techniques and the expected outcomes.
The Ensembl project (http://www.ensembl.org) provides genome resources for chordate genomes with ... more The Ensembl project (http://www.ensembl.org) provides genome resources for chordate genomes with a particular focus on human genome data as well as data for key model organisms such as mouse, rat and zebrafish. Five additional species were added in the last year including gibbon (Nomascus leucogenys) and Tasmanian devil (Sarcophilus harrisii) bringing the total number of supported species to 61 as of Ensembl release 64 (September 2011). Of these, 55 species appear on the main Ensembl website and six species are provided on the Ensembl preview site (Pre!Ensembl; http://pre .ensembl.org) with preliminary support. The past year has also seen improvements across the project.
For many years, coracoid impingement has been a well-recognized cause of anterior shoulder pain. ... more For many years, coracoid impingement has been a well-recognized cause of anterior shoulder pain. However, a precise diagnosis of coracoid impingement remains difficult in some cases due to the presence of multifactorial pathologies and a paucity of supporting evidence in the literature. This review provides an update on the current anatomical and biomechanical knowledge regarding this pathology, describes the diagnostic process, and discusses the possible treatment options, based on a systematic review of the literature. Level of evidence V.
Journal of The American Society for Mass Spectrometry, 2011
Electrospray ionization of actinyl perchlorate solutions in H 2 O with 5% by volume of dimethylfo... more Electrospray ionization of actinyl perchlorate solutions in H 2 O with 5% by volume of dimethylformamide (DMF) produced the isolatable gas-phase complexes, [An VI O 2 (DMF) 3 (H 2 O)] 2+ and [An VI O 2 (DMF) 4 ] 2+ , where An = U, Np, and Pu. Collision-induced dissociation confirmed the composition of the dipositive coordination complexes, and produced doubly-and singly-charged fragment ions. The fragmentation products reveal differences in underlying chemistries of uranyl, neptunyl, and plutonyl, including the lower stability of Np(VI) and Pu(VI) compared with U(VI).
Reported here is a comparison of electron transfer dissociation (ETD) and collision-induced disso... more Reported here is a comparison of electron transfer dissociation (ETD) and collision-induced dissociation (CID) of solvent-coordinated dipositive uranyl and plutonyl ions generated by electrospray ionization. Fundamental differences between the ETD and CID processes are apparent, as are differences between the intrinsic chemistries of uranyl and plutonyl. Reduction of both charge and oxidation state, which is inherent in ETD activation of [An(VI) O(2) (CH(3) COCH(3) )(4) ](2+) , [An(VI) O(2) (CH(3) CN)(4) ](2) , [U(VI) O(2) (CH(3) COCH(3) )(5) ](2+) and [U(VI) O(2) (CH(3) CN)(5) ](2+) (An = U or Pu), is accompanied by ligand loss. Resulting low-coordinate uranyl(V) complexes add O(2) , whereas plutonyl(V) complexes do not. In contrast, CID of the same complexes generates predominantly doubly-charged products through loss of coordinating ligands. Singly-charged CID products of [U(VI) O(2) (CH(3) COCH(3) )(4,5) ](2+) , [U(VI) O(2) (CH(3) CN)(4,5) ](2+) and [Pu(VI) O(2) (CH(3) CN)(4) ](2+) retain the hexavalent metal oxidation state with the addition of hydroxide or acetone enolate anion ligands. However, CID of [Pu(VI) O(2) (CH(3) COCH(3) )(4) ](2+) generates monopositive plutonyl(V) complexes, reflecting relatively more facile reduction of Pu(VI) to Pu(V).
The salts-yellow [Cr(NH 3) 6 ][Ag(CN) 2 ] 3 AE 2H 2 O, red [Co(NH 3) 6 ][Ag(CN) 2 ] 3 AE 2H 2 O, ... more The salts-yellow [Cr(NH 3) 6 ][Ag(CN) 2 ] 3 AE 2H 2 O, red [Co(NH 3) 6 ][Ag(CN) 2 ] 3 AE 2H 2 O, red [Co(NH 3) 6 ][Au(CN) 2 ] 3 AE 2H 2 O, pale yellow [Ru(NH 3) 6 ][Ag(CN) 2 ] 3 AE 2H 2 O, yellow K[Cr(NH 3) 6 ] 2 [Au(CN) 2 ] 7 AE 4H 2 O, and colorless [(l 2-NH 2) 2 Pt 2 (NH 3) 10 ][Au(CN) 2 ] 6 AE 5.5{OS(CH 3) 2 } AE 0.5H 2 O-have been prepared by evaporation of aqueous solutions of potassium dicyanoargenate or potassium dicyanoaurate and salts of the appropriate cations. Hydrogen bonding between the cations and the cyano groups of the anions facilitates the formation of structures with strong metallophilic interactions between the anions. Thus, the [Au(CN) 2 ] À or [Ag(CN) 2 ] À ions self-associate into linear trimers in the isostructural set of crystals, [Cr(NH 3) 6 ][Ag(CN) 2 ] 3 AE 2H 2 O (AgÁ Á ÁAg distance; 3.1610(4) Å), [Co(NH 3) 6 ][Ag(CN) 2 ] 3 AE 2H 2 O (AgÁ Á ÁAg distance; 3.1557(2) Å), [Co(NH 3) 6 ][Au(CN) 2 ] 3 AE 2H 2 O (AuÁ Á ÁAu distance; 3.0939(4) Å), and [Ru(NH 3) 6 ][Ag(CN) 2 ] 3 AE 2H 2 O (AgÁ Á ÁAg distance; 3.1584(5) Å). Crystalline [(l 2-NH 2) 2 Pt 2 (NH 3) 10 ][Au(CN) 2 ] 6 AE 5.5{OS(CH 3) 2 } AE 0.5H 2 O also contains nearly linear trimers of the dicyanoaurate ion. Yellow crystals of K[Cr(NH 3) 6 ] 2 [Au(CN) 2 ] 7 AE 4H 2 O contain a centrosymmetric, bent chain of seven dicyanoaurate ions with AuÁ Á ÁAu separations of 3.1806(3), 3.2584(4), and 3.1294(4) Å .
Recent gas-phase experimental studies suggest the presence of hypercoordinated uranyl complexes. ... more Recent gas-phase experimental studies suggest the presence of hypercoordinated uranyl complexes. Coordination of acetone (Ace) to uranyl to form hypercoordinated species is examined using density functional theory (DFT) with a range of functionals and second-order perturbation theory (MP2). Complexes with up to eight acetones were studied. It is shown that no more than six acetones can bind directly to uranium and that the observed uranyl complexes are not hypercoordinated. In addition, other more exotic species involving proton transfer between acetones and species involving enol tautomers of acetone are high-energy species that are unlikely to form.
The metalloligand [Au{C(NHMe)(NHCH 2 CH 2 NH 2)} 2 ]Cl, 1, has been prepared by the reaction of e... more The metalloligand [Au{C(NHMe)(NHCH 2 CH 2 NH 2)} 2 ]Cl, 1, has been prepared by the reaction of ethylenediamine with [Au(CNMe) 2 ]Cl. Compound 1 crystallized as a luminescent dimer with a Au 3 3 3 Au separation of 3.0224(4) Å. It reacted in solution with silver hexafluorophosphate to form the coordination polymer, {[Au{ μ-C(NHMe)(NHCH 2 CH 2 NH 2)} 2 Ag (NCMe)](PF 6) 2 } n , 2. The structure of 2 involves a chain of alternating gold(I) and silver(I) ions with a Au 3 3 3 Ag distance of 2.9694(4) Å. The reaction of the metalloligand, 1, with silver tetrafluoroborate yielded three products: the green luminescent coordination polymer, {[Au{ μ-C(NHMe)(NHCH 2 CH 2 NH 2)} 2 Ag-(NCMe)](BF 4) 2 } n , 3, which is analogous to 2; the non-luminescent binuclear complex, [Au{ μ-C(NHMe)(NHCH 2 CH 2 NH 2)} 2 Ag](BF 4) 2 , 4; and the blue luminescent complex, [{ μ-C(NHMe)NHCH 2 CH 2 NH(MeHN)C}Au 2 { μ-C(NHMe)(NHCH 2 CH 2 NH 2)} 2 Ag](BF 4) 3-3 3(MeCN), 5. Compound 5 involves a bent Au 3 3 3 Ag 3 3 3 Au cation with two different Au 3 3 3 Ag distances (2.9165(8) Å and 3.1743(8) Å). This cation self-associates through a Au 3 3 3 Au interaction of 3.0275(5) Å , which allows the formation of an extended zigzag chain of cations in 5.
The preparation and X-ray crystal structures of (CyNC)Au I CN, (n-BuNC)Au I CN, and (i-PrNC)Au I ... more The preparation and X-ray crystal structures of (CyNC)Au I CN, (n-BuNC)Au I CN, and (i-PrNC)Au I CN‚0.5CH 2 Cl 2 are reported and compared with those of (MeNC)Au I CN and (t-BuNC)Au I CN, which were previously described. These linear molecules are all organized through aurophilic interactions into three structural classes: simple chains ((CyNC)-Au I CN and (t-BuNC)Au I CN), side-by-side chains in which two strands make Au‚‚‚Au contact with each other ((n-BuNC)Au I CN), and nets in which multiple aurophilic interactions produce layers of gold(I) centers ((i-PrNC)Au I CN and (MeNC)Au I CN). All of these five solids dissolve to produce colorless, nonluminescent solutions with similar UV/vis spectra. However, each of the solids displays a unique luminescence with emission maxima occurring in the range 371−430 nm.
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