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Determinant general formula

Thus, the choice may only be made after consideration of all requirements. It is, however, not practical to analyze and compare each requirement with the hope of logically deducing the best choice. There is, unfortunately, no generalized formula for selection that is independent of the details of the intended application. Each cake requires study of the specific considerations, which are determined by the details or the separation process. [Pg.149]

This method can sometimes be used for determining the probable elemental composition of fragment ions. However, it is not as generally applicable and does not replace accurate mass measurement for determining molecular formulae and elemental compositions. [Pg.22]

In the reference cited in footnote 18, very long calculations are made by which all functions (%, 2, , A1,A2, , BlsB2, > ) are determined, and applications are developed from the general formulas so established. There are numerous applications indicated in the text illustrating the operation of this method. [Pg.362]

The eigenfunctions for / > 0 are determined in a similar manner. A general formula for the eigenfunction 5 +i , which is the starting function for evaluating the series Sni with fixed I, is obtained from equations (6.44) and (6.26a) with I = n = I ... [Pg.169]

Generally, for an n-th order polynomial, we need ( +l) rows. The first two rows are filled in with the coefficients of the polynomial in a column-wise order. The computation of the array entries is very much like the negative of a normalized determinant anchored by the first column. Even without the general formula, you may pick out the pattern as you read the following three examples. [Pg.127]

The X-ray structure of [cp Ir(CNR)Cl2], CNR = l,3,4,6-tetra-0-acetyl-2-deoxy-2-isocyano-Q,, 3-D-glucosc, has been determined.428 The synthesis of chiral complexes of Ir111 with Q-amino acid anions, L-L, of general formula [cp Ir(Cl)(L-L )] (252), and their NMR spectroscopic characterization, have been detailed. The X-ray structures of (252), L-L = L-proline and [cp Ir(Cl)(L-His-OH)]Cl, His = histidine, are described.429 C-allylglycinate binds in a terdentate manner in (253), which has been characterized by X-ray diffraction studies.430 C-vinylglycinate forms complex (254). [Pg.194]

The new silazane 5 may be reacted with activated metals, organometallic compounds or simple metal amides, or may first be transformed to its lithium salt and then reacted with metal(II) chlorides [11]. In all these cases, metal derivatives of 5 are obtained with the general formula j [Mc (/BuO)Si 9N(9M, which have no further base coordinated to the metal. So far we have synthesized amides with M = Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Ba, all elements in oxidation state +2. X-ray structure determinations have been performed on the calcium, manganese, iron, zinc, and barium derivatives. [Pg.221]

In addition to [Hg( -toluene)2-(GaCI/ )2],168 other mercury-arene complexes of general formula [I Ig( /2-arene)2-(AlCUy have been prepared.169 These include the bis(toluene), bis(o-xylene), and bis(l,2,3-trimethylbenzene) complexes 159, 160, and 161, respectively, whose structures have all been determined (Figure 8). While the arene in 159 and 161 is coordinated in an asymmetrical -fashion, the /2-1,2,3-trim ethylbenzene ligands of 160 form two nearly equal Hg-C bonds of 2.45 and 2.46 A. DFT calculations show that the Hg-arene interactions are mostly ionic. [Pg.449]

It has been several decades since oxo-centered triruthenium-carboxylate complexes with triangular cluster frameworks of Ru3(p3-0)(p-00CR)6 (R = alkyl or aryl) were first isolated [1,2]. In the early 1970s, the first oxo-centered triruthenium complex was structurally characterized by Cotton through X-ray crystal structural determination [3]. Since then, oxo-centered trinuclear ruthenium-carboxylate cluster complexes with general formula [Ru30(00CR)6(L)2L ]n+ (R = aryl or alkyl, L and... [Pg.144]

Evidently, the most interesting materials are those in a fractional oxidation state, with general formula (cation)[M(dmit)2] (n > 1), since they can exhibit both electrical and magnetic properties. Only eight such complexes have been reported so far. All of them but (BDTA)[Ni(dmit)2]2 [89] have been obtained as powders. They have in general been poorly characterized, and their stoichiometries have been determined from elemental analysis. Among these powdered compounds, the... [Pg.148]

To determine the characteristics of the 2x1 phase in the system CO/NaCl(100) from general formulae (4.3.47), we equate expressions (4.3.47) and (4.3.48) thus deriving four equations in four unknown parameters, y, ij and A ty with j = S, and A. It is noteworthy that for the spectral lines associated with local vibrations S and A, the vector k assumes two values k = 0 and k = kA (kA is a symmetric point at the boundary of the first Brillouin zone). The exact solution of the system of equations provides parameter values listed in Table 4.3.187 The same parameters were previously evaluated by formulae (4.3.49) without regard for lateral interactions of low-frequency molecular modes." As a consequence, the result was physically meaningless the quantities y and t] proved to be different for vibrations S and A (also see Table 4.3). [Pg.123]

The elemental compositions in weight percent of the four samples coded Brine Surge 1, Brine Surge 2, MBL-1A and MBL-1B collected from brine surge tank and MBL-1 sampling points were determined by EDX analysis. The clays are composed dominantly of 02 ( 70-80 wt. %) and Si ( 10-15 wt. %), and minor amounts of Na, Mg, and Al (below 5 wt.%). Trace to nil K, Ca, Fe, Mn, Zn, and Cl are also present. In MBL-1 B, however, significant amounts of Fe ( 6.5 wt. %) is present in the sample. These elemental compositions are consistent with the general formula of smectite as will be discussed later. [Pg.80]

In section 3.3 we will develop a new method of determining a formula for higher order contacts of a smooth variety X C Piv with lines in P/v- At the end we will obtain a general formula which contains the ones above as special cases. [Pg.125]

A linear molecule can have the general formulas AA, AB, or AB2. Given a molecule with the general formula AB2, which one of the following would be the most useful in determining whether the molecule was bent or linear ... [Pg.350]

We have studied several triatomic compounds of general formula XUY, where X, Y = C, N, O, and U is the uranium atom in the formal oxidation state 4+, 5+, or 6+. We have determined the vibrational frequencies for the electronic ground state of NUN, NUO+, NUO, 0U02+, and OUO+61 and have compared them with the experimental measurements performed by Zhou and coworkers.62 The CASSCF/CASPT2 method has proven to be able to reproduce experimental results with satisfactory agreement for all these systems. [Pg.268]

The MS analysis using ESI was applied for the determination of an unknown surfactant compound contained in an extract of a shampoo formulation [44]. MS leading to sequential product ions helped to identify the constituents. The MS4 experiments together with other spectral observations confirmed the hypothesis that the unknown compound was a N-( 2-aminoethyl) fatty acid amide with the general formula R-C(0)-NH(CH2-CH2-N)R/R,/. An authentic sample of the proposed laury ampho mono acetate (LAMA) (R = -CH2-CH2-OH and R" = -CH2-CH2-COOH) that was available led to the same [M + H]+ parent ion at m/z 345. The fragmentation that could be observed under ESI-FIA-MS-MS(+) conditions resulted in an intensive examination of amide surfactants. However, only two of them—lauryl diethanol amide ([M + H]+ m/z 288), a non-ionic surfactant and laurylamido-(3-propyl betaine ([M + H]+ m/z 343)—... [Pg.294]

The determination of alkyltrimethyl ammonium surfactant compounds with the general formula RN (CH3)3 X- were performed using continuous flow (CF) FAB (CF-FAB) and ESI. Dodecyl-, tetradecyl- and... [Pg.385]

The determination of alkyltrimethyl ammonium compounds with the general formula RN (CH3)3X surfactant were performed using CF-FAB and ESI. The compounds examined were dodecyl-, tetradecyl-, and hexadecyl-trimethyl ammonium compounds dissolved in water. The product ion spectra of dodecyltrimethyl ammonium compound and its methyl-deuterated homologue were presented. The product ion at m/z 60 [(CH3)3NH]+of the non-deuterated compound at m/z 228 was the only ion that shifted after deuteration to m/z 69 [38],... [Pg.386]

Carbonic acid esters (alkoxycarbonyl derivatives) are diesters of general formula R-O-CO-O-R. A single mechanism operates in the HO -catalyzed (and presumably also in the enzyme-catalyzed) hydrolysis of carbonic acid esters, namely a rate-determining addition of the base to the carbonyl C-atom to form an intermediate whose breakdown yields the drug (ROH), C02, and an alcohol (R OH) (Fig. 8.7,a) [153],... [Pg.492]

NMR spectroscopy was found to be a valuable technique for differentiation between the enantiomers of optically active compounds. The principles of the methods used to distinguish between enantiomers by means of NMR have been developed and reviewed by Mis-low and Raban (217). The best results from the point of view of the determination of optical purity and absolute configuration of chiral sulfur compounds, especially of sulfinyl compounds, have been obtained with the help of chiral solvents (218). Pirkle (86) was the first to demonstrate that enantiomeric sulfoxides have nonidentical NMR spectra when dissolved in chiral alcohols having the following general formula ... [Pg.396]


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See also in sourсe #XX -- [ Pg.33 ]




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Formulas, determination

General formula

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