Purpose: To develop a clinical infrastructure that allows for routine Monte Carlo dose calculation verification of spot scanning proton treatment plans and includes a simple biological model to aid in normal tissue protection. Materials and Methods: A graphical processing unit accelerated Monte Carlo dose engine was used as the calculation engine for dose verification on spot scanning proton plans. An infrastructure was built around this engine that allows for seamless exporting of treatment plans from the treatment planning system and importing of dose distribution from the Monte Carlo calculation via DICOM (digital imaging and communications in medicine). An easy-to-use Web-based interface was developed so that the application could be run from any computer. In addition to the standard relative biological effectiveness = 1.1 for proton therapy, a simple linear equation dependent on dose-weighted linear energy transfer was included. This was used to help detect possible high biological dose in critical structures. Results: More than 270 patients were treated at our proton center in the first year of operation. Because most plans underwent multiple iterations before final approval, more than 1000 plans have been run through the system from multiple users with minimal downtime. The average time from plan export to importing of the Monte Carlo doses was less than 15 minutes. Treatment plans have been modified based on the nominal Monte Carlo dose or the biological dose. Conclusion: Monte Carlo dose calculation verification of spot scanning proton treatment plans is feasible in a clinical environment. The 3-dimensional dose verification, particularly near heterogeneities, has resulted in plan modifications. The biological dose data provides actionable feedback for end of range effects, especially in pediatric patients.

The compound [(Cu(PPh(3))(2))(3)(HATNMe(6))](BF(4))(3) has been synthesized and characterized by X-ray crystallography, resonance Raman spectroscopy, and density functional theory (DFT) calculations. The X-ray structure of solvated [(Cu(PPh(3))(2))(3)(HATNMe(6))](BF(4))(3) [rhombohedral, R3, a = b = 21.6404(4) A, c = 53.188(3) A, alpha = beta = 90 degrees, gamma = 120 degrees] shows that the HATNMe(6) ligand is very slightly twisted. The electronic absorption spectrum of the complex in chloroform shows two bands in the visible region attributed to ligand-centered (LC) and metal-to-ligand charge-transfer (MLCT) transitions, respectively. Time-dependent DFT calculations show good agreement with experiment, with two MLCT and one LC transition predicted in the visible region (641, 540, and 500 nm). Resonance Raman spectra of the complex using discrete excitation energies between 647 and 406 nm showed a variation in enhancement patterns consistent with at least two distinct transitions. The absolute Raman cross sections have been evaluated and, through a wavepacket analysis, the amount of distortion along each vibrational mode across the Franck-Condon surface is established from the calculated dimensionless displacement (Delta) values as well as other electronic parameters. The pattern of Delta values shows good agreement with the observed calculated modes, with the MLCT transition, showing much larger Delta values for outer ring modes such as nu(93) and nu(205) than in the LC transition. This is consistent with the molecular orbitals involved in the two transitions; the donor orbitals for the LC transition have similar outer-ring bonding characteristics compared to the MLCT transition, which has no donor orbital bonding characteristics on the ligand because the donor molecular orbitals are dpi orbitals.

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