Crystal structure reinvestigation and spectroscopic analysis of tricadmium orthophosphate.

Single crystals of tricadmium orthophosphate, Cd3(PO4)2, have been synthesized successfully by the hydro-thermal route, while its powder form was obtained by a solid-solid process. The corresponding crystal structure was determined using X-ray diffraction data in the monoclinic space group P21/n. The crystal structure consists of Cd2O8 or Cd2O10 dimers linked together by PO4 tetra-hedra through sharing vertices or edges. Scanning electron microscopy (SEM) was used to investigate the morphology and to confirm the chemical composition of the synthesized powder. Infrared analysis corroborates the presence of isolated phosphate tetra-hedrons in the structure. UV-Visible studies showed an absorbance peak at 289 nm and a band gap energy of 3.85 eV, as determined by the Kubelka-Munk model.

Crystal structure of SrCo4(OH)(PO4)3, a new hy-droxy-phosphate.

Single crystals of strontium tetra-cobalt tris-(orthophosphate) hydroxide, SrCo4(OH)(PO4)3, were grown serendipitously under hydro-thermal conditions at 473 K. The crystal structure consists of undulating chains of edge-sharing [CoO6] octa-hedra that are linked into (010) layers by common vertices between chains. Adjacent layers are linked along [010] into a framework structure by tetra-hedral [CoO4] units and by PO4 tetra-hedra. The framework delimits channels extending along [100] in which the eleven-coordinate strontium cations are situated. Bifurcated O-H⋯O hydrogen bonds of weak strengths consolidate the crystal packing. The title compound was also characterized by infrared spectroscopy.

Histological surprise of parotid tuberculosis: about two cases.

Parotid tuberculosis remains a very rare localization in the Department of Otolaryngology and Cervico-Facial Surgery (ENT) sphere. It is presented in the form of a deceptive clinical picture causing confusion with other pathologies of the parotid gland, including tumor pathology. In addition, its lack of knowledge by practitioners increases the risk of missing the diagnosis. Often, the diagnosis is a histological surprise on a piece of excision after an exploratory parotidectomy. However, its treatment is primarily medical if the positive diagnosis is well established. We report medical observation of two new cases aged 44 and 45 respectively, who consult our center for parotid swelling. Radiological examinations were in favor of intraparotid cystic lesions. Both patients benefited from an excision whose histopathological study was in favor of primary parotid tuberculosis. The subsequent evolution was favorable under antituberculous treatment.

Crystal structure of Ba2Co(BO3)2.

Single crystals of dibarium cobalt(II) bis-(orthoborate), Ba2Co(BO3)2, have been obtained from the melt. The crystal structure is composed of two isolated (BO3)3- triangles linked to Co2+ cations. The resulting [CoO5] square pyramids and the borate anions make up branched rows extending parallel to [010]. The barium cations occupy two sites in the voids of this arrangement and exhibit coordination numbers of nine each. A comparison with the structures of other A 2 M(BO3)2 compounds reveals a unique five-coordination of the small metal M in the title compound instead of four- or six-coordination for the other A 2 M(BO3)2 compounds with M = Cu, Zn, Mg, Ca, or Cd.

Pleomorphic adenoma of the soft palate: major tumor in a minor gland.

Salivary gland tumors are a relatively rare and morphologically diverse group of lesions. Pleomorphic adenoma is a benign tumor of the salivary gland that consists of a combination of epithelial and mesenchymal elements. The tumor most commonly arises from the parotid (60-70%) or submandibular glands. It develops less frequently in a minor salivary gland, presenting as an intraoral mass depend on the soft palate. We describe a case of benign pleomorphic adenoma of soft palate in a 45 year old female with computed tomography and histopathological findings. This patient presented in ENT department with history of gradually increasing mass lesion in the palatal region over a period of few months.

Contralateral facial nerve palsy following mandibular second molar removal: is there co-relation or just coincidence?

Peripheral facial nerve palsy (FNP) is the most common cranial nerves neuropathy. It is very rare during dental treatment. Classically, it begins immediately after the injection of local anaesthetic into the region of inferior dental foramen and it's homolateral to the injection. Recovery takes a few hours, normally as long the anaesthetic lasts. The authors present a 44-year-old patient who presented a contralateral delayed-onset facial paralysis arising from dental procedure and discuss the plausible pathogenesis mechanism of happen and a possible relationship between dental procedure and contralateral FNP.

Castle man disease: a case report and review of the literature.

The Castleman disease (CD) is a rare disease of unknown etiology, characterized histologically by angiofollicular lymphoid hyperplasia. It comes in two forms, unicentric and multicentric. We report a case of Castleman disease in a 58 year old man, who had consulted for chronic cervical lymphadenopathy. This case was a multicenteric and rapidly fatal despite aggressive treatment with corticosteroids, and chemotherapy.

Dipotassium tristrontium dimanganese tris(diphosphate).

The structure of the title mixed trimetallic diphosphate, K(2)Sr(3)Mn(2)(P(2)O(7))(3), is constructed of a three-dimensional matrix composed of SrO(8-10), MnO(5) and PO(4) polyhedra. The sharing of O atoms between these polyhedra creates tunnels of large dimensions parallel to (010), in which are found columns of K(+) ions. Thus, the presence of several cations differing in size in the solid matrix leads to the formation of large tunnels and potential conductivity.

Sodium silver tricobalt bis(diphosphate) and sodium silver copper(II) diphosphate.

The crystal structures of two new diphosphates, sodium silver tricobalt bis(diphosphate), (Na(1.42)Ag(0.58))Co(3)(P(2)O(7))(2), and sodium silver copper(II) diphosphate, (Na(1.12)Ag(0.88))CuP(2)O(7), provide examples of the effect of mixing Na and Ag in the same site of known host phosphate compounds. The small differences in ionic radii of the two monocations do not lead to significant differences in the structural details. In the latter compound, the Cu atom lies on an inversion center.

Dilithium barium diphosphate.

The crystal structure of the novel title diphosphate, Li(2)BaP(2)O(7), exists with a three-dimensional lattice composed of BaO(9) polyhedra linked to corner- and edge-sharing P(2)O(7) diphosphate groups, forming layers parallel to the (010) plane, the layers being linked by P[bond]O[bond]Ba bridges. Tunnels thus created between the layers are occupied by Li(+) cations, two of which lie on twofold axes.

NaMn(6)(P(2)O(7))(2)(P(3)O(10)) and KCd(6)(P(2)O(7))(2)(P(3)O(10)).

The crystal structures of two new diphosphates, sodium hexamanganese bis(diphosphate) triphosphate, NaMn(6)(P(2)O(7))(2)(P(3)O(10)), and potassium hexacadmium bis(diphosphate) triphosphate, KCd(6)(P(2)O(7))(2)(P(3)O(10)), confirm the rigidity of the M(6)(P(2)O(7))(2)(P(3)O(10)) matrix (M is Mn or Cd) and the relatively fixed dimensions of the tunnels extending in the a direction of the unit cell. The compounds are isomorphous; the P(2)O(7)(4-) anion and the alkali metal cations lie on mirror planes. Bond-valence analysis of the bonding details of the atoms found within the tunnels permits a prediction of the conductivity.

Barium tetraphosphate.

The structure of the low-temperature form of barium tetraphosphate, Ba(3)P(4)O(13), shows the tetraphosphate to exist in an S conformation.

New Metal Oxamates as Precursors of Low-Dimensional Heterobimetallics.

The goal of this work was to synthesize new molecular bricks which could be used as precursors of heterobimetallic low-dimensional compounds. Along this line, four compounds have been synthesized and structurally characterized, namely (NBu(4))(2)[Ni(Cl(2)opba)] (1), (NBu(4))(2)[Cu(Cl(2)opba)] (2), (NBu(4))(5)[Mn(Cl(2)opba)(DMSO)(2)](4) (3), and Cu(en)(2)[Mn(Cl(2)opba)(H(2)O)(2)](2).2DMSO (4), with Cl(2)opba = (4,5-dichloro-o-phenylene)bis(oxamato), NBu(4) = tetra-n-butylammonium, en = ethylenediamine, and DMSO = dimethyl sulfoxide. Compounds 1 and 2 are isostructural; they crystallize in the monoclinic system, space group C2/c, Z = 4, with a = 18.708(2) Å, b = 17.525(2) Å, c = 14.763(9) Å, and beta = 92.03(4) degrees for 1 and a = 18.928(2) Å, b = 17.634(2) Å, c = 14.704(9) Å, and beta = 92.38(3) degrees for 2. 3 crystallizes in the tetragonal system, space group P&fourmacr;2(1)c, Z = 2, with a = 26.295(10) Å and c = 12.342(7) Å. The structure shows a random occupation of the metal site by Mn(III) and Mn(II) ions in 3/4 and 1/4 ratios, respectively. 4 crystallizes in the triclinic system, space group P&onemacr;, Z = 1, with a = 7.066(7) Å, b = 11.844(1) Å, c = 14.292(5) Å, alpha = 105.64(2) degrees, beta = 97.67(5) degrees, and gamma = 102.13(3) degrees. The structure consists of Mn(III)Cu(II)Mn(III) trinuclear species, with Cu-O-Mn bridges involving oxygen atoms of the oxamato groups already linked to the metal atom. The magnetic properties of compounds 1-4 have been investigated and quantitatively interpreted. For 3, this magnetic investigation has been performed on a single crystal, which allows us to determine unambiguously the sign of the axial zero-field splitting parameter for the Mn(III) ion. The potentialities of these new molecular bricks have been discussed.