bluuebunny/crossref_metadata_2025_split huggingface dataset:
Zum Wirkungsmechanismus von 1-Nitroso-3-nitro-1-methylguanidin (NNMG) bei der Mutationsauslösung / The Mode of Action of 1-Nitroso-3-nitro-1-methyl-guanidine (NNMG) in Mutagenesis
Authors: Süssmuth R. , Lingens F. 
Published: March 2015

1. The stability of NNMG with respect to pH was investigated. A maximum, with a half-life of 40 hours, was found in phosphate-citric acid buffer at pH 5. The stability decreases quickly with increasing concentration of hydroxyl ions. At the optimal mutation rate (pH 6, 37°, and shaking) the half-live is only 14,4 hours.
2. NNMG uptake (using labelled NNMG) and mutation rate in the range pH 3,5 — 8,0 show an optimum at pH 6,0/6,5 for both Escherichia coli B and the red ad- mutant E 188 of Saccharomyces cerevisiae. The pH-dependence of NNMG uptake and mutation rate is similar.
3. The methylation of nucleic acids by means of [3H]-methyl-NNMG or [14C] -methyl-NNMG in phosphate-citric acid at 37° while shaking increases with the growing concentration of hydroxyl ions. At the optimal mutation rate, however, NNMG methylates relatively poor.
4. Incorporation of radioactive NNMG into Escherichia coli B results in labelling of nucleic acids and proteins. The labelling of DNA shows an optimum at pH 6. The extent of methylation was found to be higher in vivo than in vitro.
5. In the presence of cysteine or β-mercaptoethanol nucleic acids are methylated more intensively than in the cysteine-free control experiment. After one hour the methylation was about twentyfold higher in the presence of cysteine or β-mercaptoethanol compared to the cysteine-free control experiment. The methylation in presence of SH-compounds shows a maximum at pH 6. The explanation of both a higher methylation rate and its optimum at pH 6 suggests the activation of methylation by means of sulphhydryl-groups.
Properties of the Photoactive Chlorophyll-aII in Photosynthesis
Authors: Döring G. , Renger G. , Vater J. , Witt H. T. 
Published: March 2015

1. The complete difference spectrum of the reaction of the photoactive chlorophyll-an is presented.
2. The reaction of excited chlorophyll-aII is of the type of a sensitizer. It is not engaged directly in the electron transfers. This is in contrast to the photoactive chlorophyll-aI which is an electron donor in its excited state.
3. The chlorophyll-aII-reaction can be separated from the overall reaction by heating chloroplasts 5 min at 50°C.
4. Chlorophyll-an is the reaction center of the well-known poison DCMU.
5. Properties of chlorophyll-aII are depicted in Tab. 1. They are compared with those of chlorophyll-aI and the O2-evolution system.
Immunologische Studien am Omentum.
Authors: Krüsmann W. F. , Kasemir H. , Ax W. , Fischer H. 
Published: March 2015

An thymektomierten, scheinoperierten und normalen NMRI-Mäusen wurde mit 3H-Thymidin autoradiographisch die Mesothelzell-Proliferation am Omentum majus nach intraperitonealer Stimulierung mit Schaferythrozyten untersucht.
Bei thymektomierten Tieren war die Mesothelproliferation am 1. und 2. Tag nach der Injektion im Vergleich zu scheinoperierten Tieren hochsignifikant vermindert.
Bei normalen Tieren war die Mesothelproliferation nach Sekundärstimulus geringer als nach Primärstimulus. Diese Befunde und ihre Deutung werden diskutiert.
Polarographic Behaviour of 3-Mercapto-1,2-propanediol at d.m.e.
Authors: Saxena R. S. , Singh Pratap 
Published: March 2015

The polarographic behaviour of 3-mercapto-1, 2-propanediol (TSH) at the d.m.e. has been investigated in presence of 0.1 M NaClO4 and 0.001% Triton X-100 with respect to the effects of changes in pH. concentration of TSH, drop time and temperature on the wave characteristics. A single well defined irreversible anodic wave was obtained over the entire pH range (1.84 — 12.3) which was found to shift towards the more negative potential with the increase in pH. The E½ values obtained at different pH were used to evaluate the dissociation constant of sulphydryl group; the pK value has been found to be 9.25.
The linearity of id with TSH concentration provides a rapid and precise method for the determination of TSH to 0.1 mmole. The values of Kinetic parameters-formal rate constant (K°b,h) and transfer coefficient (a) have been evaluated by applying Koutecky’s theoretical treatment as extended by Meites and Israel and were found to be 1.738 × 10-4 cm/sec and 0.277 respectively.
Die Aminosäuresequenz des Ornithin und Lysin enthaltenden Mureins einiger Stämme von Lactobacillus bifidus aus dem Pansen /The amino acid sequence of the ornithine and lysine containing mureins of some strains of Lactobacillus bifidus isolated from rumen
Authors: Holzapfel Wilhelm , Scardovi Vittoria , Kandler Otto 
Published: March 2015

Cell walls of six strains of Lactobacillus bifidus (recently classified as Bifidobacterium globosum) isolated from the rumen of sheep were isolated by lysing the cells with glass beads followed by tryptic digestion. No teichoic acid could be found. The polysaccharide consists of galactose, rhamnose and glucosamine. The murein (peptidoglycan) contains MurNAc, GlcNH2NAc, Glu, Ala, and diamino acids in a molar ratio of 1:1:1:5:1. Both diamino acids, lysine and ornithine are present. In two strains they occur in about equal amounts, while in the other four strains ornithine is predominant. The lysis of the cell walls by lysozyme resulted in a mixture of two types of muropeptides: One contains lysine, the other ornithine.
The amino acid sequence was determined by analysing the oligopeptides arising during acid partial hydrolysis. It was shown, that the tetrapeptides attached to the muramic acid are equal to those of other mureins: L-Ala-γ-D-Glu-L-Lys (L-Orn) -D-Ala. Glutamic acid is probably amidated, since the total hydrolysate contained slightly more than one mole of NH3 per mole of glutamic acid. The cross-liking peptide is a tri-alanine, which is bound to the ω-aminogroup of the diamino acid of one tetrapeptid and to the C-terminal D-alanine of another. Since about 2 —4% of the alanine is N-terminal in the cell wall, 10 to 20% of the interpeptide bridges are probably not cross linked. In addition 2 — 3% of the diamino acids are ω-N-terminal and therefore not substituted by a trialanine. A small percentage of D-alanine and of the diamino acids is C-terminal. The latter indicates, that some of the peptide subunits are incomplete i.e.. the terminal D-alanine is missing.
Regulation glykolytischen Umsatzes durch Synthese und Abbau von Enzymen Regulation of Glycolysis by the Synthesis and Degradation of Enzymes
Authors: Kahl G. , Lange H. , Rosenstock G. 
Published: March 2015

Differential derepression of the genome of potato tuber cells causes the onset of a vigorous metabolic activity, which is initiated by rapid synthesis of different RNA species, various proteins and phospholipids. Consequently enhanced respiration and the build up of cell compartments such as ribosomes and mitochondria as well as the performance of cell divisions and suberization of new-formed cell walls occur. Although there is an activation of metabolism in general with a concomitant rise in concentration of most glycolytic metabolites — as was proved for fructose-1.6-diphosphate, dihydroxyacetone, glyceraldehade-3-phosphate, phosphoenolepyruvate and pyruvate — the activities of the corresponding enzymes do not reflect these uniform metabolic changes. Aldolase and in a pronounced manner enolase and glutamate — pyruvate — transaminase lower their activities suddenly after derepression. The activity of triosephosphateisomerase remains constant. In contrast phosphoglyceromutase, pyruvate kinase and to a lower extent malic enzyme enhance their action during the same time.
Without doubt, differential lowering and enhancing the activity of glycolytic chain constituents at the same time is an important regulatory mechanism of the cell. The activation represents de novo synthesis of the protein concerned whereas the inactivation depends largely on protein synthesis. This is clearly shown by experiments with inhibitors of protein synthesis.
It is proposed that this differential synthesis and degradation represent a “long-time-regulation” of enzymatic activity of the cell in contrast to the known “short-time-regulation” by feedback or competition.
The Integumentary Mucous Secretions of the Earth Worm Megascolex mauritii
Authors: Krishnan N. , Rajulu G. Sundara 
Published: March 2015

A histochemical study of the epidermal gland secretions in earth worm Megascolex mauritii has been made. The secretions of the aluminous gland is a glyco or mucoprotein and that of the mucous gland cells is an acid mucopolysaccharide. Two types of mucous glands are present in the epidermis, the small and large mucous glands, secreting hyaluronic acid and highly acidic sulphated mucopolysaccharide, respectively.
The functions of the secretions from these glands are investigated. The albuminous and small gland cells secrete mucin under normal conditions and this mucin keeps the body surface moist and serves as lubricant during locomotion. The large mucous gland secretes only after irritation and its secretion may be an alarm pheromone.
Photolysis of 5-Bromouracil and Some Related Compounds in Solution
Authors: Campbell J. M. , Sonntag C. von , Schulte-Frohlinde D. 
Published: March 2015

The steady state photolysis of 5-bromouracil (BU) in aqueous solution has been studied as a function of wavelength, pH, temperature, and hydrogen-donor concentration. Under all conditions studied, the primary reaction is shown to be C-Br bond cleavage followed by abstraction from the hydrogen-donor to give uracil and HBr. At pH &gt; 12 further products are formed. In deoxygenated aqueous solution at pH 6, 20°C, and 254 nm, the quantum yield of BU consumption, Φ (-BU), is 1.8 × 10-3 independent of hydrogen-donor type or concentration (e.g. 3 × 10-2 to 2 M MeOH). With increasing pH, Φ (-BU) increases stepwise to 0.012 at pH 10 and to 0.28 at pH 14. pK-values calculated from these data are the same as ground state pK values. Φ (-BU) increases with temperature with an activation energy of approx. 3.4 kcal/mol. Φ (-BU) increases with photon energy. Above 2 M MeOH Φ (-BU) increases reaching Φ (-BU) = 0.025 in neat MeOH. Similar high, solvent dependent, values are obtained for other hydrogen-donor solvents. In neat organic solvents an additional reaction with BU induced by solvent radicals was observed.
These results have been explained in terms of a homolytic dissociation of the C-Br bond of the excited BU followed by recombination or H atom abstraction by the radicals. At high hydrogen-donor concentration H atom abstraction can compete with cage recombination. A comparison has been made between BU photolysis in organic, hydrogendonor solvents and BU photolysis within the DNA of bacteria or phages. It has been concluded that the much higher quantum yields observed for chain breaks in the photolysis of DNA containing BU compared to photolysis of BU in aqueous solution is due to the high local concentration of hydrogen-donors (sugar molecules) within the DNA molecule, even in dilute aqueous solution.
Die Kristallstrukturen der Verbindungen Ca5Si3 und Ca5Ge3 / The Crystal Structures of Ca5Si3 and Ca5Ge3
Authors: Eisenmann B. , Schäfer H. 
Published: March 2015

The new compounds Ca5Si3 and Ca5Ge3 were prepared and their structure determined.
They crystallize in the Cr5B3-structure type.
Spekktroskopische Untersuchungen in der Festkörperchemie, IX / Spectroscopic Investigations in the Solid-State Chemistry, IX
Authors: Burkert Paul K. , Hutter Frank , Koth Detlev 
Published: March 2015

The four 185Re, 187Re—NQR-transitions of RbReO4 were measured. From the NQR-coupling constants, asymmetry-parameter and normal temperature-coefficient in the range of 77-300°K one can conclude, that the anomalons temperature dependence of the NQR-frequencies of NH4ReO4 is not caused by the absolute values of certain lattice parameters.
An experimental correlation of the Re—NQR-coupling constants of scheelite-structured perrhenates with the length of the elementar cell was found and discussed.
Die Kristallstruktur von KTlF4 / Crystal Structure of KTlF4
Authors: Hebecker Ch. 
Published: March 2015

The results of X-ray structure determinations on single crystals of KTlF4 are reported.
The unit cell is trigonal with α = 8.025, c = 10.16 A, Z = 6; space group: P 31 - C2
3. KTlF4 is a new superstructure variant of the CaF2-type. Each Tl is coordinated by 7, K by 8 resp. 9 F. Other A+B3+F4-type compounds (A+ = Na, Ag, K; B3+ = In, Tl, Ln) are isostructural with KTlF4.
Die Komplexbildung der Zitronensäure, II.
Authors: Veith Josef A. , Wiese Günther 
Published: March 2015

Mixtures of citric acid (H3Ci) and Fe(NO3)3 with variable molar ratios (H3Ci/Fe(NO3)3 from 0 to 2.55) were titrated with NaOH. The change in pH and the occurring inflection points were registered with a potentiograph (Fig. 1). For each inflection point (I.P.) the existing H3Ci/Fe(NO3)3 molar ratio was plotted against the NaOH/Fe(NO3)3 molar ratio which existed at the corresponding inflection point (at most three I.P. for each titration curve). The coefficients ej, fj and gj for each dehydrated
Fe-Ci-complex [Fefj(OH)gj-3ejCicj](gj-3fj)⁻ with j = 1, 2, . . . ,
could be calculated from the points of intersection (Pj) in the x-y-diagram (Fig. 2). Thus, the following three Fe-Ci-complexes were calculated:
From the 1st I.P. [Fe10(OH)18Ci5]3- with its maximum at pH ≃ 4.3.
From the 2nd I.P. [Fe5(OH)9Ci4]6- with its maximum at pH ≃ 8.0.
From the 3rd I.P. [Fe4(OH)11Ci]2- with its maximum at pH ≃ 10.1.
The range of their existence as functions of H3Ci/Fe(NO3)3 ratios (Fig. 3 and 4) and pH (Fig. 4) is discussed.
Notizen: Radiation Chemistry of DNA-Model Compounds, VII. On the Formation of 5-Deoxy-D-erythro-pentos-4-ulose and the Identification of Twelve Further Products from γ-Irradiated Aqueous Solutions of Ribose-5-phosphate
Authors: Stelter Lothar , von Sonntag Clemens , Schulte-Frohlinde Dietrich 
Published: March 2015

Different mechanisms are considered to explain the formation of 5-deoxy-D-erythropentos-4-ulose in the γ-radiolysis of ribose-5-phosphate in aqueous solution. On the basis of deuterium labelling experiments one mechanism involving an enol as an intermediate could be excluded.
The identification of twelve further radiolysis products from ribose-5-phosphate is reported.
Über die Koordinationspolymeren M(II)[Pt(CN)6], II Schwingungsspektren und Kraftkonstanten / Coordination Polymers M(II)[Pt(CN)6], II Vibrational Spectra and Force Constants
Authors: Siebert Hans , Weise Manfred 
Published: March 2015

The IR spectra (33-4000 cm-1) and the RAMAN spectra (0-2500 cm-1) of the complexes M(II)[Pt(CN)6] (M = Mg, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd) have been recorded. In the region 33-300 cm-1, the IR spectra of the isotopic compounds with 64Zn and 68Zn68Zn and with 58Ni and 62Ni have been obtained. The observed frequencies are assigned to the normal modes of the lattices.
A normal coordinate analysis has been carried out for the above coordination polymers. The force constants of the Pt(CN)6 moiety are with one exception identical with those obtained for the isolated ion. The CN valency force constant is slightly shifted to higher values. The valency force constants of the coordinative bonds M(II)-N are in the range 0,1-1 mdyn/Å. This variability is considered to stem primarly from ligand field effects.
Darstellung und Röntgenstrukturanalyse von (CH3)3C-C7H7Mo(CO)3 (1-6- η-7-tert-Butyl-cycloheptatrien)(tricarbonyl)molybdän(0) / Synthesis and Crystal Structure of (CH3)3C-C7H7Mo(CO)3 (1-6-η-7-tert-Butyl-cycloheptatriene)(tricarbonyl)molybdenum(0)
Authors: Tremmel Peter O. , Weidenhammer Klaus , Wienand Henning , Ziegler Manfred L. 
Published: March 2015

The title compound has been synthesized by three different methods and its structure determined from three dimensional X-ray data by Patterson and Fourier methods. The crystals are triclinic with unit cell dimensions a = 1022.60 ± 0.07 pm, b = 638.69 ± 0.27 pm, c = 1478.00 ± 0.19 pm, α = 78.48 ±0.02°, β = 131.049 ± 0.008°, γ = 87.16 ± 0.03 °, space group Ci
1—PT and Z = 2. Least squares refinement by use of 2160 independent reflections measured on a diffractometer has reached R = 5.4%.
There are discrete (CH3)3C—C7H7Mo(CO)3 molecules, the central molybdenum atom is octahedrally coordinated.
Notizen: 1.3-Di(tert-butyl)-2.4-dichlor-diazaphosphaarsetidin / 1,3-Di(tert-butyl)-2,4-dichlorodiazaphosphaarsetidine
Authors: Scherer Otto J. , Schnabl Günter 
Published: March 2015

Kleine, ausschließlich Heteroatome enthaltende Element-Stickstoff-Ringe werden vielfach bevorzugt dann gebildet, wenn an das N-Atom eine tert-Butyl- oder Trimethylsilyl-Gruppe gebunden ist1.
Ausgehend vom zweifach tert-Butyl-substituierten Phosphatriazen (1)2 erhält man durch 1.2-Addition von AsCl3 die offenkettige Zwischenverbindung3 2, die ihrerseits durch cyclisierende Si-N-Spaltung 1.3-Di(tert-butyl)-2.4-dichlor-diazaphosphaarsetidin (3) bildet6
Photoelektronenspektren von Verbindungen der V. Hauptgruppe, ΙII Methylhalogenverbindungen MeEHaI2 und Me2EHal / Photoelectron Spectra of Group V Compounds, III Methylhalogen Compounds MeEHal2 and Me2EHal
Authors: Elbel Susanne , Dieck Heindirk Tom 
Published: March 2015

The He I photoelectron spectra of certain MeEHal2 and Me2EHal compounds (E = (N), P, As, Sb; Hal = (F), Cl, Br, J; Me = CH3) are interpreted in terms of a “composite molecule” approach derived for C3vCs systems. Although an “internal standard” is missing here, substituent group-orbitals (nHal, C—H) may be classified with respect to their orientations in space (R, V, T). Ionisation energies are assigned according to this assumption.
PE data of the isoelectronic EMe3/EHal3 compounds and of related molecules (Me2EH, MePH2, CF3PBr2) as well as EHMO calculations with partial inclusion of spin orbit coupling are used to confirm the assignments given for Me2EHal/MeEHal2 series.
Correlations between PE ionisation energies (e.g. nE (IE)) and molecular or atomic properties are critically revised and discussed.
Massenspektrometrische Untersuchungen an Borchelaten, III. Massenspektrometrische Fragmentierung von Fluorobor- und Phenylborchelaten.
Authors: Hohaus Eberhard , Riepe Wolfgang 
Published: March 2015

Mass spectra of several fluoroboron and phenylboron chelates were compared with regard to the influence of the boron substituent F and C6H5.
The fragmentation pattern depends very strongly on the type of the substituent.
In the case of the fluorine substituent, the three bonding states of boron will be reached preferably by opening the chelate ring. For the substituent C6H5 this state of boron will be reached by elimination of C6H5.
Reaktion von 1.4-Dienen mit Metallkomplexen, I Darstellung und Röntgenstrukturanalyse eines π-enyl-Komplexes der Zusammensetzung (C8H13PdCl)2/ Reaction of 1,4-Dienes with Metal Complexes, I Synthesis and X-ray Structure Determination of a π-enyl Complex of Composition (C8H18PdCl)2
Authors: Feldhaus Peter , Ratka Richard , Schmid Hermann , Ziegler Manfred L. 
Published: March 2015

Reaction of (C6H5CN)2PdCl2 and 1,3-dimethylenecyclohexane led to an exocyclic π-enyl complex of formula (C8H13PdCl)2-bis(η3-2-methylene-6-methylcyclohexyl)(di-µ-chloro)-dipalladium. IR and 1H NMR data are in agreement with this formulation.
The compound is monoclinic, with unit cell dimensions α = 499.97 ± 0.08, b =1342.26 ± 0.19, c =1379.60 ± 0.20 pm, β = 99.43 ± 0.02°, space group C5h
2-P21/C, Ζ = 2, dX-ray = 1.83 g/cm3.
The structure was determined from three-dimensional X-ray data by Patterson and Fourier methods. Least squares refinement by use of 1045 independent reflections has reached R1 = 5.6%.
Mechanismus und Kinetik der Zersetzung von Methan-Wasser-Gemischen im kalten Plasma.
Authors: Simionescu Cr. I. , Dumitriu S. , Popa V. I. 
Published: March 2015

In the present paper the mechanism and kinetics of methane-water mixtures decomposition in cold plasma are discussed. It was found that nature and composition of the products depend on reaction time, ratio of the two components, and how long the products are in contact after the decomposition was performed.
Reactions in the decomposition system generally follow two mechanisms: corresponding to the discharge phase and to postreaction one. The highest yield of formaldehyde was obtained for the ratio methane water of 0.6-1 and two minutes of discharge.
Phosphorus Compounds with the VI B Group Elements
Authors: Monteil Y. , Vincent H. 
Published: March 2015

The preparation and the properties of phosphorus sulfides and selenides are reviewed.
The exact number of phosphorus sulfides and selenides has been determined from the phase diagram. Phosphorus does not react with tellurium. The ternary diagram P—S—Se shows no P—S—Se compounds. The domains of P—S and P—Se glasses has been also determined. IR and mass spectrometry show that phosphorus sulfides and selenides have a tetrahedral arrangement of P atoms close to that of white phosphorus.
Die Hydrolyse einiger Borsäureester unter Base-Einfluß in nichtwäßrigen Lösungsmitteln / The Hydrolysis of Some Tris(organyloxy)boranes under Alkaline Influence in Non-aqueous Solvents
Authors: Heller G. , Ross H. 
Published: March 2015

The hydrolysis of tris(organyloxy)boranes (boric acid esters) in organic solvents in the presence of KOH leading to potassium polyborates (free from water of crystallization) is studied as to the influences of (a) the reaction medium (ethanol or ligroine/ethanol), (b) the concentration of water, (c) the organyl group of the boric acid ester (methyl, isopropyl, or phenyl), (d) the time of stay of the precipitated insoluble polyborates under the mother liquor (15 to 61850 s), and (e) the temperature during precipitation and the time of stay (—18 to + 60°C).
In the first stage of the reaction, during precipitation time, ester hydrolysis is followed by condensation, while aggregation and desorption processes occur between the time of precipitation and filtration.
Austauschreaktionen an komplexgebundenen Liganden von Elementen der V. Hauptgruppe, V1 Darstellung und Reaktionen von Komplexen des Typs π-C5H5Mn(CO)2L (L = Phosphid, Amid) / Exchange Reactions at Complexed Ligands of Elements of Group V B1 / Preparation and Reactions of Complexes of the Type π-C5H5Mn(CO)2L (L = phosphide, amide)
Authors: Höfler Mathias , Hausmann Heinz , Saal Wilhelm 
Published: March 2015

The reduction of the complexes C5H5Mn(CO)2L (L=P(C6H5)2Cl, P(C6H5)(Et)Cl and P(C6H5)Cl2) with Na in liquid NH3 yields the complexes C5H5Mn(CO)2L′ (L′=P(C6H5)2Na, P(C6H5)(Et)Na and P(C6H5)Na2).
The reaction of these complexes with CH3J and of CpMn(CO)2PØ2Na with H2O, CH2Cl2, CCl4, J2 and CH3COCl are described. Furthermore it has been found, that n-butyl-lithium yields C5H5Mn(CO)2NMe2Li if reacted with C5H5Mn(CO)2NMe2H.
Adsorption von Aceton an Magnesiumoxid.
Authors: Koubowetz Franz , Noller Heinrich , Latzel Johannes 
Published: March 2015

The adsorption of acetone on MgO was studied by IR spectroscopy, the desorption products were analyzed with a mass spectrometer. Furthermore, the heat of adsorption and the coverage of the surface were calculated from adsorption isothermes measured at various temperatures.
Acetone is adsorbed over (weak) hydrogen bonds to surface hydroxyl groups as well as coordinatively bound to the cation Mg2+. This bonding to the cations causes strong shifts of the carbonyl band (up to 100 cm-1) and the CH3 bands (Δν≈55 cm-1) to lower wavenumbers. At 120°C, desorption of acetone, and at 320°C and 400°C of methane is detected. Using d6-acetone or D2O, the methane observed can be shown to be formed from hydrogen of acetone rather than with participation of hydrogen of surface hydroxyl groups.
Neue intermetallische Verbindungen im anti-PbFCl-Strukturtyp.
Authors: Dörrscheidt Wolfgang , Schäfer Herbert 
Published: March 2015

Three new intermetallic compounds CaMnGe, SrMnGe and BaMnGe have been prepared. They crystallize tetragonal in the anti-PbFCl-structure type with the following constants :
CaMnGe: a = 4.23(1); c = 7.27(1); c/a = 1.72,
SrMnGe: a = 4.40(1); c = 7.52(1); c/a = 1.71,
BaMnGe: a = 4.50(1); c = 7.92(1); c/a = 1.76.