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State function preparation

He2 ICl conformer using action spectroscopy to find the bound-free continuum associated with the He + He IC1(B, V = 3) dissociation limit. It would also be insightful to perform time-resolved experiments on the different conformers of these systems to directly monitor the kinetics for forming the different products and intermediates as a function of the different excited-state levels prepared. [Pg.416]

In accordance with the provisions of the Dietary supplement Health and Education Act 1994, in the United States botanical dosage forms can be marketed as dietary supplements provided the label makes no medical claim however, structure-function claim is allowed. In most countries other than the United States, botanical preparations are regulated as drugs thus posing a different set of challenges. This fact must be taken into consideration in standard setting. [Pg.414]

R. W. Field I must apologize for not being sufficiently clear about the excitation scheme we use for our acetylene experiments. Although the initial and final states are both on the acetylene X1 g surface, the final state we prepare is the result of two electronic transitions (A X followed by A —X) rather than one vibrational-rotational infrared or Raman transition. There is a profound difference between the knowledge of the excitation function needed to describe electronic versus vibrational processes. [Pg.602]

Thus the response of a spatially uniform system in thermodynamic equilibrium is always characterized by translationally invariant and temporaly stationary after-effect functions. This article is restricted to a discussion of systems which prior to an application of an external perturbation are uniform and in equilibrium. The condition expressed by Eq. (7) must be satisfied. Caution must be exercised in applying linear response theory to problems in double resonance spectroscopy where non-equilibrium initial states are prepared. Having dispensed with this caveat, we adopt Eq. (7) in the remainder of this review article. [Pg.12]

A lot of thermodynamics makes use of the important concept of state function, which is a property with a value that depends only on the current state of the system and is independent of the manner in which the state was prepared. For example, a beaker containing 100 g of water at 25°C has the same temperature as 100 g of water that has been heated to 100°C and then allowed to cool to 25°C. Internal energy is also a state function so the internal energy of the beaker of water at 25°C is the same no matter what its history of preparation. State functions may be either intensive or extensive temperature is an intensive state function internal energy is an extensive state function. [Pg.394]

Lowe et al. [7] and Frias et al. [8] described complexes of cyclene-based molecules with lanthanoids. A gadolinium complex which would exhibit pH-dependent relaxivity thanks to a switch in hydration state was prepared. [7] Cyclene bore a sulphonamide substituent in order to achieve a variation of the coordination environment of the lanthanide centre as a function of pH (Scheme 7). [Pg.92]

Volumes have been written about the red herring known as Schrodinger s cat. Without science writers looking for sensation, it is difficult to see how such nonsense could ever become a topic for serious scientific discussion. Any linear differential equation has an infinity of solutions and a linear combination of any two of these is another solution. To describe situations of physical interest such an equation is correctly prepared by the specification of appropriate boundary conditions, which eliminate the bulk of all possible solutions as irrelevant. Schrodinger s equation is a linear differential equation of the Sturm-Liouville type. It has solutions, known as eigenfunctions, the sum total of which constitutes a state function or wave function, which carries... [Pg.49]

This condition, which amounts to uniform compression of the atom, when simulated numerically, shifts the electronic energy to higher levels, and eventually leads to ionization. It means that environmental pressure activates the atom, promotes it into the valence state and prepares it for chemical reaction. The activation consists therein that sufficient energy is transferred to a valence electron to decouple it from the core. The wave function of such a freed electron (eqns 3.36, 5.31) remains constant within the ionization sphere. [Pg.244]

Nobel laureate in Physics) in 1924. In quantum mechanics, two ensembles which show the same distributions for all the observables are said to be in the same state. Although this notion is being introduced for statistical ensembles, it can also be applied to each individual microsystem (see, for example, ref. 8), because all the members of the ensemble are identical, non-interacting and identically prepared (Fig. 1.4). Each state is described by a state function, ip (see, for example, ref. 3). This state function should contain the information about the probability of each outcome of the measurement of any observable of the ensemble. The wave nature of matter, for example the interference phenomena observed with small particles, requires that such state fimctions can be superposed just like ordinary waves. Thus, they are also called wavefunctions and act as probability amplitude functions. [Pg.11]

We now consider an experiment in which molecules in the ground-state vibrational level gf> are excited by a delta-function light pulse to the coupled N-level system, whereupon the fluorescence from the excited state thereby prepared to some final ground-state level /> is monitored as a function of time. (Note that this implies some degree of spectral resolution of the fluorescence.) The fluorescence signal in such an experiment is.a generalization of Eq. (3.2) ... [Pg.282]

Here fp) represents the nonstationary excited-state wave function prepared by the pump pulse and we have introduced the impulsive polarization P t,At), that is, the polarization for an an idealized -function probe pulse. [Pg.760]

As often happens in chemistry, a simple application of a law leads to profound developments. Because of the first law, chemists have been able to develop a common quantitative scale for internal energies and other state functions of all compounds. The idea is quite simple. Since every chemical compound may be prepared from elements or other compounds, either through a single reaction or... [Pg.476]

To describe a system completely, we must indicate its temperature, its pressure, and the kinds and amounts of substances present. When we have done this, we have specified the state of the system. Any property that has a unique value for a specified state of a system is said to be a function of state, or a state function. For example, a sample of pure water at 20 °C (293.15 K) and under a pressure of 100 kPa is in a specified state. The density of water in this state is 0.99820 g/mL. We can establish that this density is a unique value—a function of state—in the following way Obtain three different samples of water—one purified by extensive distillation of groundwater one synthesized by burning pure H2(g) in pure 02(g) and one prepared by driving off the water of hydration from CUSO4 5 H2O and condensing the gaseous water to a liquid. The densities of the three different samples for the state that we specified will all be the same 0.99820 g/mL. Thus, the value of a function of state depends on the state of the system, and not on how that state was established. [Pg.260]

The present chapter is the first of four chapters that are concerned with basis functions and basis sets. In Chapter 7, we go on to consider the expansion of the two-electron helium ground-state wave function in products of atomic basis functions, preparing ourselves for the construction of general molecular basis sets in Chapter 8. The evaluation of integrals over atomic basis functions is discussed in Chapter 9. [Pg.201]


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See also in sourсe #XX -- [ Pg.10 , Pg.14 ]




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Functionalization preparation

Functions state function

Prepared states

State functions

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