what is the criterion for oscillator strength of dark state vs. bright states obtained from LR-TDDFT (Casida approach)?

03 April 2017 2,853 2 View

Which one is more pi-deficient: bipyridine or benzimidazole?

I need comparative data about pi-electron distribution over benzimidazole and bipyridine groups. Is there any simple way to calculate it? Furthermore, if the above character will change when we...

05 June 2014 8,593 3 View

Is there any direct way to extract the "electronic density of excited state" from GAMESS (US) output?

I did a excited state calculation with GAMESS by adding tdprt=.true. which writes some properties of the excited state in output (for example, the dipole moment.) Now, I'd like to know about...

03 April 2014 1,232 1 View

How to set a different "k" value in Charge scaling function for C-PCM?

Dear GAMESS users. As far as I know, the C-PCM model, calculates the surface charge for a conductor continuum, and then re-normalize it with f=(epsilon-1)/(epsilon+k). If there is any way to...

31 December 2013 2,822 0 View

How to predict the deprotonation of a molecule in a solvent?

I want to do ab-initio calculation for an organic D-pai-A dye in presence of a solvent, and this molecule has a cyanoacetic group as an anchoring group, I am not sure about its neutral or anion...

09 October 2013 5,774 15 View

Where can I find the parameters needed to define acetonitrile as a solvent in gamess input?

Acetonitrile in GAMESS. I want to do DFT calculation including PCM model in Gamess, but I have problem to define that as a solvent. As my best knowledge, there is many solvents in DMS table but I...

09 October 2013 9,325 1 View

How to set nstate for TDDFT calculations?

I want to calculate UV/Vis for an organic dye, and I found that increasing the "nstates" in tddft calculations, changes the value of first excitation energy, for example when I change nstate from...

09 October 2013 547 5 View

What is the "Analytical form of Hessian matrix for freq calculation"?

I am looking for the analytical derivative algorithms which are accessible in quantum chemistry, If in g09 or Gamess the harmonic approximation used to make analytical terms for energy derivatives?

07 August 2013 2,199 1 View

What is the physical origin of the numerical value of fwhm (~0.4 eV, or 3000cm-1 in gausssum) in uv/vis spectrum ?

Usually, fwhm considered about 3000 cm-1 in many papers, but this is a very big number in comparison with the corresponding value for Gaussian broadening, in text books--it is about 0.05 cm-1 for...

05 June 2013 10,000 4 View

MD MOE RMSD

How to calculate the RMSD values for a MD simulation using MOE?

07 August 2021 0 0 View

MD MOE RMSD

How to calculate the RMSD values for a MD simulation using MOE?

07 August 2021 0 0 View

fatal error

When I tried to energy minimization my system, I got fatal error as below. Fatal error: Atomtype opls_116 not found Although I've already added this line: ; include water #include "oplsaa.ff/spc.itp" to [molecultype] directive in my topology.

16 June 2021 0 0 View

fatal error

When I tried to energy minimization my system, I got fatal error as below. Fatal error: Atomtype opls_116 not found Although I've already added this line: ; include water #include "oplsaa.ff/spc.itp" to [molecultype] directive in my topology.

16 June 2021 0 0 View

fatal error

When I tried to energy minimization my system, I got fatal error as below. Fatal error: Atomtype opls_116 not found Although I've already added this line: ; include water #include "oplsaa.ff/spc.itp" to [molecultype] directive in my topology.

16 June 2021 0 0 View

fatal error

When I tried to energy minimization my system, I got fatal error as below. Fatal error: Atomtype opls_116 not found Although I've already added this line: ; include water #include "oplsaa.ff/spc.itp" to [molecultype] directive in my topology.

16 June 2021 0 0 View

flexibility of polymers chain

effect of double bond on the flexibility of polymers

07 April 2021 0 0 View

Formulation of polymer color flakes

I am writing to request some information for making polymer color flakes. I would appreciate the help.

17 March 2021 0 0 View

Could you recommend any books about Number Theory?

Beginner level books. High level books. Analytical Number Theory. Algebraic Number Theory. Combinatorical Number Theory. Books about partitions. Books about primes.

03 March 2021 7,174 5 View

What kind of fluid could I use for a pitfall trap that also does not invalidate molecular testing?

Hi, I want to start testing pitfall trap to obtain ants samples, but I need to conduct molecular analysis on those insects. So, what kind of fluid can I use? Ethanol expires too early and I need...

03 March 2021 5,978 5 View