Atomic Definition and 812 Threads

Does atoms in a crystal have energy states like electronic states? it is according to Einstein relation for harmonic oscillator.E=nhw

hello, I was wondering how the atomic radii where calculated. I have used the formula r=\frac{a_{o}n}{z*/n*} where z* is effective nuclear charge and n* is the effective principal quantum number but it seems to give me a bit different radii compared to the ones on Wikipedia...

I know that for hydrogenic wavefunctions, the parity of a given state is (-1)^l . But does this mean that the probability densities for any such wavefunction is ALWAYS even? I'm trying to understand the Stark effect, and specifically why there is no first-order correction for he ground state...

1. I am a metal. My atomic radius is smaller than the atomic radius of the element with one fewer protons, but my +1 ionic radius is larger than the +1 ionic radius of the element with one fewer protons. Of the two elements in my group that have biological importance, I am the one with higher...

Hello my name is Dax, I'm currently in the world building stage of a science fiction I am writing and I came here to bounce some questions off of you fine people. My question is regarding atomic numbers of elements on the periodic table and weather it could be possible that negative atomic...

I am a retired electrical engineer, now able to get back to studying what I really enjoy - mathematics and physics. As a genuine old geezer, my modern physics knowledge, which was never very deep, is now way out of date. I purchased a copy of "Modern Physics", by Kenneth Krane, and have been...

I would be most grateful for some tips of interactive software, which shows the hybridized atomic orbitals overlapping in the molecule (I don't mean resulting molecular orbitals but atomic orbitals of which overlapping forms MO). And does this works also in Mathematica?

hi, ive got a really simple question. niels bohr proposed a model of the atom in witch the electron cannot fall into any energy state but must fall be in certain discreet values and this helps explain why the electron doesn't clumb with the nucleus almost instantly. not the atom needed to...

Hi, i have a question about the center of mass change during photon emission in terms of the polarization of the emitted photon. first, a few facts are as follows: i) selection rule: if delta m=0, that means p (atomic recoil) = p (photon) in magnitude. This is of pi transition and...

Homework Statement This isn't a homework question, but I will try and follow the template. I am confused about the relationship between the absorbtion and emission spectrums for hydrogen. I was taught that in the balmer series for hydrogen, when an electron moves from the n=1 level to...

Suppose that I have an atom in one corner of a room, and I fire a photon toward the opposite corner (and assume that it is absorbed there into the wall). There is essentially zero probability that that photon will interact with the atom (either be captured, or stimulate emission, or whatever)...

Homework Statement An atom or ion with one electron has energy levels E_n=-A/n^2. Tw neighboring lines in its spectrum at room temperature have wavelengths \lambda_1=97.5 nm and \lambda_2=102.8 nm. (Note that hc=1.240\times 10^{-6} eV m). (a)What is the constant A? (b) Identify the atom...

Have there been any experiments using atomic clocks underground as a comparison to those on the Earth's surface?

Hi guys I've been having some trouble plotting the p(x) and d(xy) atomic orbitals on Matlab. I have been given that p(x) = x*e^-(x^2 + y^2 + z^2)^0.5 and d(xy) = x*y*e^-(x^2 + y^2 x^2)^0.5 Now I want to plot these orbitals on MATLAB using mesh or the surf command and then plot the...

Hey guys, I was looking at both the time-dependent and time-independent schrodinger equations, and I notice that we often choose to solve these in spherical coordinates. I understand that we do this because they are convenient for problems with azimuthal symmetry. However, how do we know that...

http://gizmodo.com/5793309/worlds-first-single+electron-transistor-works-like-a-teeny-tiny-etch+a+sketch About the page above, atomic force microscope makes tunelling. But I didn't understand how it made tunneling? Would you explain how tunelling appears in a atomic force microscobe, please?

Hello, I have a rather conceptual question I couldn't really find an answer to yet. The electric field lines of an isolated resting electron would simply point from everywhere in space towards the position the electron is located in, with a length inversely proportional to the squared distance...

I remember a professor mentioning something about how scientists did this when we were discussing the history of the periodic table (they originally ordered it by atomic mass). I can't seem to find an answer online without digging through a lot of stuff...there was one article on this topic...

Hello. I read about fast neutron therapy for cancer and the therapy uses a beam of high energy neutrons. How do you excite a particle to make it have "higher" energy.

I just got an Atomic Clock and googled how they work. It says it picks up the Atoms in the Air and sets the Clock from finding out the Energy they emit or something like this. Can you tell me what I am missing or how they work?

Hi all, This is a question regarding stress and strain. Can someone please explain the concepts of stress and strain in atomic level? My understanding is as follows.Let us consider a metal bar or rod that is subjected to tension.The load applied to the bar will be try to elongate the...

So I've been studying forbidden transitions and metastable states in atoms, etc., and I was just wondering if there is such a thing as forbidden bound-free transitions? I've only encountered bound-bound. For example, if you have a neutral Helium atom with two electrons, I understand how...

Hi all, This is a question regarding stress and strain. Can someone please explain the concepts of stress and strain in atomic level? My understanding is as follows.Let us consider a metal bar or rod that is subjected to tension.The load applied to the bar will be try to elongate the...

I've been looking online at multiple resources and seem to be getting conflicting answers. http://www.sciencegeek.net/tables/AtomicRadius.pdf - Where He is slightly smaller than H http://intro.chem.okstate.edu/1314F00/Lecture/Chapter7/ATRADIID.DIR_PICT0003.gif - Where H is smaller than He...

Why does the atomic radii get smaller from the left to right of a period but get bigger from top to bottom of a group? Wikipedia says in an article about electron shielding "Next we take Beryllium, Be as an example. It has 2 electrons in the 2s shell and thus, these electrons will repel each...

Have atomic models been proposed that do not have overlapping N levels?

can intense gravity like this in black holes stop atomic motion/jiggling ? if it does , where does the kinetic energy go ? does it radiate before entering a black hole ?

I've examined in lab how a capacitor acts within a circuit. In a case where we charge a capacitor in series with a bulb and then another capacitor, I get the circuit in charging.png. So let's say electrons in the circuit flow from the positive end to the negative end and the circuit flows like...

I am interested in knowing if the inside radius of the inner most part of the electron cloud is a constant versus Z. For example is it always the Bohr radius, or does this inner radius change as a function of Z? What is the experimental evidence?

Hello everyone. I have a problem I can't figure out. Let's say that we start off with UO2 fuel. Knowing the density (and enrichment) we can calculate the number densities of the constituents (i.e. U-238, U-235, U-234, O-16). Suppose now that the fuel is burned to a certain exposure. A...

This was just posted today, and looks interesting http://arxiv.org/pdf/1309.1137.pdf A New Generation of Atomic Clocks: Accuracy and Stability at the 10-18 Level B. J. Bloom et al The exquisite control exhibited over quantum states of individual particles has revolutionized the field of...

how do i determine the different atomic positions of iron (bcc) as the number of atom increases.

Hi, I am having a problem on career choice. I like astrophysics, but I am also interested in atomic physics. What do atomic physicists do as their job, can they get employment in industries?

1. Homework Statement Draw an LCAO representation of all of the bonding orbitals for C2H2O. Be sure to clearly state the hybridization of the two carbons and the oxygen in addition to drawing the orbital representation. Also show clearly what orbital any unshared pairs occupy. 2...

Hi, Please help me I am lost. I particle in a box model , equation for energy show that the energy increases as n increases, but in Borh's theory n^2 is in the denominator showing that as n increase, the energy decrease, I see the condradiction here. Am I right?

Is there any thing that could, or any way to increase the atomic decay rate of already unstable elements, such as the radio active elements. magnetically or otherwise, even if the thought is only plausible or otherwise theory, I wouldn't mind hearing it. A thought accord to me, what if...

Hello, A sinusoidally driven and undisturbed cantilever of an atomic force microscope (AFM) oscillates ideally in a sinusoidal fashion but the motion of the cantilever (time-domain trajectory) can become more complicated when it is disturbed by the inter-atomic forces as the cantilever taps...

In his paper, Chou et. al., 2010 has demonstrated that an atomic clock at the height of our head ticks faster than an atomic clock at the height of our feet. I was thinking that one electromagnetic process can be substituted with any other - so that corresponding atoms in our head tick faster...

To excite an electron in the atom from lower state to higher you need an EM field of frequency that matches the energy difference between those levels. How does the near-resonance transition work then? Thanks in advance.

A thought crossed my mind about the idea of atomic computers. In short, I have no clue as to whether such a thing is feasible, already in the works, or just a bunch of nonsense, which is why I decided to bring it up here and see if anyone could offer some insight into this idea. If so, I’d...

Hello everyone, I would like to buy some Si wafer with SiO2 layer on it. The manufacturer told me that they obtain the SiO2 with a wet oxidation process. My question is, would this layer be amorphous or crystalline or polycrystalline? Thanks!

Hi, Simply, what is "zeta" in atomic shells and what is its relationship with orbital angular momentum (L)? How is it used in quantum physics?

I happened across this little thing in a formula and I can't find what it stands for in any book/ website :confused: I think it stands for the ground state of an element, but I want to clarify first :smile: The symbol is E0 Its in this formula, which is derived from the energy of an...

Homework Statement Q1. Briefly explain the relevance of the Pauli exclusion principle for the structure of the periodic table of the elements. Q2. What is the maximum number of electrons that can be located in an atomic subshell with quantum numbers n and L? Briefly expain your answer...

Homework Statement The following photon wavelengths are observed in absorption at room temperature from an ionized atomic gas with a single electron orbiting the nucleus: λ= 13:5 nm, 11:4 nm, 10:8 nm. Use this data to determine the effective Rydberg constant and the nuclear charge...

Hi , well this is just a idea that came up when thinking about a certain problem in physics. Now it's late and I don't wan to be long but is it possible or has it been done , a device that could for example hold back lighter nuclei and let through heavier ones or vice versa? Well imagine a...

[SIZE="4"]Assume we have a concentration of any specific material (in mg/M). Let's say for example: Ag (Z=47) with concentration 10 mg/M in water (H2O, Z=7.42). How can I calculate the effective atomic number (Zeff.) for the silver-water mixture if the concentration of silver was 10 mg/M for...

Hey guys, I was doing some research and I am confused since I can't seem to get a straight answer. I wanted to know what the diameters/radii of protons and electrons are. But no place I go to agrees on the numbers. The general trend for protons is somewhere around 10^-15, but I've seen...

How is this possible if quarks are point particles?

Hello all, What is mean the Ritz Wavelengths in the NIST Atomic Spectra Database? Why the Ritz or Observed value for some Wavelength are very different? Thanks, Lil